The Golden State Warriors and Boston Celtics have quite a bit in common if you can get past the three championship rings currently on the fingers of Stephen Curry, Draymond Green, Klay Thompson, and Steve Kerr.

Both teams drafted and developed the biggest stars on their roster. Both teams added one key starter via a trade that was doubted at the time. Both teams hit on late first round draft picks in the 20s to augment their cores with critical young talent. Both teams are used to making deep playoff runs. The Celtics haven’t raised a title banner since 2008, but they do deserve credit for making four trips to the Eastern Conference Finals in the last six seasons.

The Warriors and Celtics have one other big thing in common. Both of them lost a superstar in free agency but still rebounded to reach the NBA Finals.

In the summer of 2019, Kevin Durant left the Warriors and Kyrie Irving left the Celtics to team up together on the Brooklyn Nets. Their departures threatened to close the championship window for both teams. Three seasons later, there’s no doubt Boston got even better without Irving. The Warriors certainly aren’t as dominant as they were at their peak with Durant, but they were still good enough to win the West with relative ease.

Here’s how the Warriors and Celtics survived the loss of a superstar to reach the Finals.

The Warriors didn’t need Kevin Durant to make the NBA Finals

Golden State never needed Durant to win a championship. The Warriors won it all in 2015 behind the Curry-Thompson-Green core that they drafted and developed. The next year they finished with the best regular season record ever at 73-9 overall, but famously lost in the NBA Finals to LeBron James and the Cleveland Cavaliers in seven games.

Durant signed with the Warriors the following summer when the NBA salary cap experienced a rare spike. The Warriors won consecutive NBA championships in 2017 and 2018, and then lost to the Toronto Raptors in the 2019 Finals after Thompson and Durant each suffered injuries that would keep them out for more than a year. Durant entered free agency shortly after the injury, and confirmed the worst kept secret in sports when he left the Warriors for New York to team with Irving.

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How the Warriors used Kevin Durant’s departure to add Andrew Wiggins

Find the full story of why Durant left the Warriors here. The main thing you need to know about the post-KD reboot is that the superstar forward didn’t leave Golden State for nothing.

When Durant agreed to join the Nets, Golden State was able to turn it into a sign-and-trade, with D’Angelo Russell as the main piece coming back. The Warriors had to give Russell a four-year, $117 million deal, include a first round pick in the transaction (that ultimately turned into a second rounder), and salary dump Andre Iguodala to pull it off. There were serious questions about Russell’s fit with the Warriors at the time, as well as extreme skepticism on if he could live up to the money, but the Warriors made the move for one big reason: they wanted to maintain a high salary slot so they could potentially add another big piece to the team via a trade with the existing roster already way over the salary cap.

Russell played 33 games with the Warriors before they found a trade they liked, moving him to the Minnesota Timberwolves for Andrew Wiggins and a 2022 first round pick.

While the pick alone made the deal seem worth it at the time, most people were ready to write off Wiggins. He had a reputation as an inefficient scorer with a hot-and-cold motor who couldn’t live up to his max contract or his former No. 1 overall draft status.

It took some time for Wiggins to get comfortable with a new role in Golden State, but he broke out in a big way this year. He was named an All-Star starter (even if he didn’t deserve it), and has blossomed into a go-to wing stopper during this postseason. The same physical gifts that once made Wiggins a can’t-miss prospect in the draft — his speed, his length, his ridiculous explosiveness as a leaper — have been channeled on the defensive end in a masterful way. Wiggins’ 17.2 points per game is his lowest scoring average since his rookie year in 2015, but it feels like this is the best basketball he’s ever played.

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The Warriors’ 3 lottery picks have been a mixed bag, but they found a young star late in the first round

The year after Durant left in free agency, the Warriors went 15-50 overall as Thompson recovered from his torn ACL and Curry was limited to only five games because of a broken hand. The Warriors drew the No. 2 overall pick in the 2020 draft, and selected James Wiseman over LaMelo Ball. Wiseman has not played this season as he recovers from a knee injury, but could still be a big part of the Warriors’ future.

The Warriors went 39-33 in 2020-2021 season but missed the playoffs when they lost to the Memphis Grizzlies in the play-in tournament. That left Golden State with two lottery picks: their own at No. 14, and the Timberwolves’ selection from the Wiggins-Russell swap at No. 7 overall. The Warriors selected Jonathan Kuminga with the seventh pick, and Moses Moody with pick No. 14. Neither rookie made a huge impact this season — save for some solid Moody minutes off the bench in the conference finals — but both project as rotation contributors at minimum moving forward.

The Warriors’ three lottery picks post-Durant have yet to yield a star, but they found one at the end of the draft in 2019 after their Finals loss to the Raptors. The Warriors selected Jordan Poole out of Michigan at No. 28 overall. After developing in the G League and being buried deep on the Golden State bench for his first few years, Poole emerged as an offensive supernova this season. His ability to create his own shot off the bounce has been a major boon for Golden State, giving the team another three-level scorer with a sorely needed injection of speed and explosiveness attacking the basket.

The Warriors also found another gem late in the first round when they selected UCLA big man Kevon Looney with the No. 15 overall pick in 2015. It took Looney a few years to become a contributor, but he’s been incredibly valuable on this postseason run. His screening ability makes him a natural fit on offense with the old championship core. He’s also been the Warriors’ best rebounder, an efficient interior scorer, and a surprisingly switchable defender in this postseason when Golden State has needed him.

Ask the Mavericks about how good Looney is. He felt as important as any player during the Warriors’ win the Western Conference Finals.

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The Warriors also nailed their minimum free agent signings

The Warriors were way over the salary cap entering free agency in the summer of 2021. The team decided to let go of wing Kelly Oubre, who often lacked the processing speed to be ideal fit for the roster, and then went to work with minimum signings. They picked up three key players on those minimum deals:

• Otto Porter Jr.
• Andre Iguodala
• Nemanja Bjelica

Porter has been a great fit with the Warriors in particular as a 6’10 wing who can space the floor, play help defense, and even create a midrange bucket in the pinch. He’s been a key part of the playoff rotation since the postseason began. Iguodala and Bjelica were also valuable additions at the end of the roster even while the former has been sidelined for the playoffs with injury.

The other big piece the Warriors added on the margins was already on the roster. Golden State was expected to keep Avery Bradley with the 15th and final spot on the roster, but instead opted for Gary Payton II. GPII eventually worked his way into the rotation and then the starting lineup for the playoffs with his tenacious on-ball defense and infusion of athleticism. Payton was injured in the Warriors’ second round series against the Grizzlies, but could return for the Finals. His excellent point of attack defense would be a major factor in this series if he’s healthy.

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Why Kyrie Irving left the Boston Celtics

The Celtics were coming off a conference finals appearance in 2017 when they embarked on an offseason that would change the franchise.

The Celtics won the draft lottery with Brooklyn’s pick from the old Kevin Garnett-Paul Pierce trade, but they decided to trade back from No. 1 to No. 3 with the Philadelphia 76ers. The Sixers took Washington point guard Markelle Fultz. The Celtics drafted Jayson Tatum.

The next big move was the trade for Irving. The Celtics sent out All-Star guard Isaiah Thomas, Jae Crowder, and Brooklyn’s unprotected 2018 pick for Irving, who had become dissatisfied as LeBron James’ sidekick in Cleveland.

The Celtics were damn good in two seasons with Irving, but couldn’t break through to the Finals. In his first year with the team, Irving put up sparkling numbers, but eventually needed knee surgery and missed the playoffs. The young Celtics went to the conference finals without him. The 2019 team couldn’t live up to sky-high preseason expectations, and Irving appeared to be discontented most of the year. He put up terrible playoff numbers as the Celtics lost to the Bucks in the second round. Then he skipped town to join forces with Durant in Brooklyn. Here’s a longer explanation of why Kyrie left Boston.

Irving wasn’t the only major free agent the Celtics lost in 2019. Al Horford also left Boston to sign a big money deal with the Philadelphia 76ers. The Celtics signed Kemba Walker to a $141 million max contract to replace them.

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The Celtics were patient with their core of Jayson Tatum, Jaylen Brown, and Marcus Smart

The biggest reason for the Celtics’ success has been their ability to draft, develop, and be patient with their core.

The Celtics have missed the playoffs exactly once in the last 15 years, and the one time they did the franchise selected Marcus Smart with the No. 7 overall pick in the 2014 draft. Smart was never really a traditional point guard, but he carved out a niche as one of the league’s best perimeter defenders while steadily impriving as a shooter. Smart is a three-time First Team All-Defense selection and was named Defensive Player of the year this season.

Jaylen Brown was drafted No. 3 overall in the 2016 draft with the Nets’ pick. Tatum was taken No. 3 overall the following year, again thanks to cashing in the pick that originally belonged to Brooklyn.

Tatum eventually developed into the superstar and primary offensive option. Brown slotted in as the No. 2 option as a big, athletic wing who consistently improved as a three-point shooter. Smart was the lockdown defender, occasional playmaker, and streaky shooter who connected Boston’s other stars.

The Celtics went to the conference finals again in the bubble in 2020 with Walker and Gordon Hayward starring alongside the young core, but they were dropped by the Heat in six games. Last year, the Celtics were steamrolled by Irving and Durant’s Nets as Walker was rendered ineffective with a knee injury. Still, the Tatum-Brown-Smart trio remained, and felt poised for a bright future.

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The Celtics rescued Al Horford from OKC and watched him resurrect his career

Horford’s decision to sign in Philadelphia didn’t work out for himself or the team. He was never a natural fit with Joel Embiid and Ben Simmons, and ultimately was traded to the Oklahoma City Thunder for Danny Green. The Thunder had no intentions of using Horford to help them win as they continued their rebuild, and ultimately shut him down after only 28 games last season.

The Celtics traded the No. 16 overall pick and Walker to get Horford at the start of the offseason. Few thought Horford could still be a dependable contributor on a contender at age-35, but he’s apparently found the fountain of youth this season. He has been excellent on both ends of the court throughout this run, shooting 43.2 percent from three in the playoffs while providing fantastic defense all over the floor. He feels like Boston’s essential glue guy: the heady veteran who can be a hub on both ends with the versatility to space the floor and defend smaller players.

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The Celtics nailed two late first round draft picks

It’s hard to remember now, but Robert Williams was once considered a lottery talent in the 2017 draft before making a surprising decision to return to Texas A&M. His draft stock fell a bit the next year, dropping to the No. 27 overall pick where the Celtics were happy to take him.

The Celtics nailed a late first rounder again the next year by taking Grant Williams with the No. 22 overall pick in the 2019 draft. Robert Williams has added a 7’6 wingspan, elite athleticism, and skilled rim protection to the Celtics. Grant Williams has added switchable defense and surprising long range shooting (41 percent form three this year) to the front court, as well.

Those two hits in the draft have been enough to cover up the Celtics making some serious draft blunders. They whiffed on Romeo Langford and Aaron Nesmith with the No. 14 overall pick in 2019 and 2020 respectively. They traded the picks that became Desmond Bane and Matisse Thybulle. Payton Pritchard, drafted No. 26 overall in 2020, has also given the Celtics some deep bench minutes on this playoff run, but it’s tempting to think of how perfectly Bane would have fit with Boston’s core.

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The Celtics added two more in-season reinforcements

On Feb. 10, with the Celtics riding a six-game winning streak to dig themselves out of a slow start, Boston made two moves to beef up the rotation for the playoffs. First, they acquired Derrick White from the San Antonio Spurs for Josh Richardson, Romeo Langford, a 2022 first-round draft pick, and a top-1 protected 2028 first-round pick swap. Then the Celtics landed another former player in Daniel Theis from the Houston Rockets in exchange for Dennis Schroder, Bruno Fernando and Enes Freedom.

White’s incredible ability to dart around screens has made the Celtics’ defense even scarier. Theis has added more depth to the front court, and has seen minutes when Robert Williams missed time with a knee injury. Boston was already trending up before the trade deadline, but the moves to bolster their roster in-season were key to this NBA Finals push.

The Warriors and Celtics both made the NBA Finals by sticking to their system

Last season, players like Kelly Oubre and a rookie center in James Wiseman didn’t feel like good fits for the Warriors’ read-and-react offense based around constant ball movement and screening. They were replaced by a players you fit the system better in Kevon Looney, Otto Porter Jr., and Gary Payton II.

The Celtics eventually figured out a system that fit their talent after a slow start under first year head coach Ime Udoka. Boston sat at No. 9 in the Eastern Conference on Feb. 1 but quickly turned things around behind a historically strong defense. The Celtics smothered opponents for the rest of the season with their huge and skilled defensive lineups that switched almost everything while mixing in different coverages at times to keep teams confused.

The Warriors already had a championship-caliber system that orbited around Curry, Green, and Thompson. They found players who could fit it. The Celtics had a success young core with Tatum, Brown, and Smart, and eventually figured out the right scheme and right role players to complement them.

It sure feels like the two best teams in the league are still standing. It’s going to be a great NBA Finals.