It didn't take long for Boston Celtics president of basketball operations Brad Stevens to make his first move. On Friday, the Celtics sent point guard Kemba Walker, the No. 16 pick in this year's draft and a 2025 second-round pick to the Oklahoma City Thunder for center Al Horford, center Moses Brown and a 2023 second-round pick. Horford is a former Celtic.
Who starts at point for Boston? How should the team handle the sudden logjam at center? Is Walker a fit next to Shai Gilgeous-Alexander?
Let's hand out trade grades for both teams.
Boston Celtics get: Al Horford, Moses Brown, 2023 second-round pick
Oklahoma City Thunder get: Kemba Walker, 2021 first-round pick (No. 16), 2025 second-round pick
Boston Celtics: C+
Brad Stevens' first move as president of basketball operations, a role he has held for just two weeks, is a logical one that also raises questions about further changes to the Celtics' roster. Let's unpack them.
First: Does Boston plan to use Horford as a power forward? The last team to try that, the Philadelphia 76ers, got burned badly. Philadelphia was outscored by 0.2 points per 100 possessions when Horford played alongside Joel Embiid -- the biggest reason the Sixers quickly moved Horford to Oklahoma City after just one season -- but had an impressive plus-5.8 net rating when he played center with Embiid off the court, per my analysis of lineup data from NBA Advanced Stats.
Part of the reason Horford bounced back in the shortened season he played for the Thunder, which lasted just 28 games before he was shut down so the team could look at younger prospects (and, ahem, maybe not win so much), was moving exclusively to center. Aside from a handful of minutes with Mike Muscala, Horford was almost always Oklahoma City's biggest player on the court.
Yet this trade creates a sizable logjam for the Celtics in the middle. They add both Horford and Brown, who averaged 14.5 points and 15 rebounds per 36 minutes replacing Horford as the Thunder's starter in the middle down the stretch, to a group that already includes Tristan Thompson and Robert Williams. (Fellow Boston centers Tacko Fall and Luke Kornet are free agents, and this trade could spell the end of their time with the team.)
Back in 2018-19, Horford's last season with the Celtics before signing in Philadelphia as an unrestricted free agent, he played almost exclusively at center during the regular season (1,800 of his 1,972 minutes, per my analysis). However, Stevens played him regularly with physical center Aron Baynes in the playoffs, using that duo together as starters in five of the team's nine games.
It's possible Boston could get away with playing Horford alongside Thompson or Williams at times because of his ability to stretch the floor. The Celtics don't have the same kind of non-shooter elsewhere like Ben Simmons, who complicated the 76ers' big lineups, and neither Thompson nor Williams is a post-up threat like Embiid. Still, defending power forwards on the perimeter would be a big ask for Horford at age 35.
Second: Who plays point guard after Walker's departure? Presumably the answer is Marcus Smart, who has split time on and off the ball depending on Walker's availability. Still, Smart played more than two-thirds of his minutes with another ball handler last season. Boston's only real alternative there is second-year guard Payton Pritchard, who played well as a rookie but doesn't seem ready to move into a starting role just yet.
After trading a point guard for two centers, the Celtics could use a trade to rebalance their roster by, say, trading a center for a point guard.
In financial terms, this move is a clear win for Boston. Swapping Walker for Horford saves $9 million in 2021-22 salary. Take away the $3.1 million first-year salary for the No. 16 pick in this year's draft and the Celtics will start free agency under the tax line in terms of commitments. Boston can now re-sign wing Evan Fournier and go modestly into the tax or replace him using the non-taxpayer midlevel exception and plausibly avoid it altogether.
The financial gains are potentially greater in 2022-23, when Horford's $26.5 million salary is guaranteed for just $14.5 million unless the Celtics reach the NBA Finals this season. Waiving Horford and stretching his guarantee could allow Boston to create somewhere in the neighborhood of $20 million in cap space to retool around Jaylen Brown and Jayson Tatum, pending possible extensions for Smart and Williams.
Because of the painful sacrifices needed to create cap room, notably renouncing the rights to Smart, the Celtics might simply prefer to keep Horford for 2022-23. Even then his declining salary will be $11.1 million less than Walker's salary in the final year of their contracts.
From a basketball standpoint, I'm not sure Boston got any better with this deal. After accounting for the higher replacement level for centers than point guards, Walker was a more productive player in 2020-21 than Horford, and point guard is probably now a bigger need than center was for the Celtics beforehand. To make this deal work out, Boston will have to take full advantage of the cap flexibility it creates.
Oklahoma City Thunder: A-
This trade is yet another example of Thunder executive vice president and general manager Sam Presti getting first-round picks on both ends of a trade. Presti all but pioneered the move with Kurt Thomas, getting two first-round picks -- one of them used on Serge Ibaka -- to take his salary from the tax-avoiding Phoenix Suns in 2007 before getting a third from the San Antonio Spurs at the 2008 trade deadline.
Presti did it again with Chris Paul, who came with a bevy of first-round picks when acquired from the Houston Rockets and fetched one on his way to the Phoenix Suns. Now it's happened a third time with Horford.
As a refresher, Oklahoma City got a 2025 first-round pick from the 76ers (top-six protected) along with the rights to 2020 second-round pick Theo Maledon and international stash Vasilije Micic as payment for taking on Horford's contract in exchange for a package headlined by Danny Green. Surely, part of Presti's thinking was that the Thunder could rebuild Horford's value, and that's more or less what's happened.
Now, Oklahoma City gets yet another first-round pick -- the team's third in the 2021 draft to go along with the Thunder's own and one from the Miami Heat that could be swapped for the Houston Rockets' pick if that drops to No. 5 in next week's lottery -- to take on Walker's contract for Horford.
Can Presti pull it off again by trading Walker for value on his way out? It's certainly possible. If Walker can stay healthy next season, his contract might not look so onerous with a year and a half remaining, particularly if Oklahoma City is again willing to utilize future cap space to take on a longer-term deal.
Although Walker hasn't been the All-Star point guard the Celtics thought they were getting in 2019 free agency, he hasn't been bad when on the court. Walker might benefit from the kind of conservative management of playing time the Thunder utilized with Horford, who sat out to rest on a frequent basis before being shut down. Horford crossed the 30-minute mark just three times in the 28 games he played.
That said, Walker is a trickier fit with Oklahoma City's current roster than Horford was. The Thunder didn't have any top prospects at center blocked by Horford's playing time. Point guard is a different story. Oklahoma City has Maledon, who started 49 games as a rookie, and also wants to get Shai Gilgeous-Alexander regular minutes at the point.
Gilgeous-Alexander did begin last season starting alongside veteran point guard George Hill, but Hill's thumb injury quickly solved that issue, as he played just 14 games for the Thunder before being traded at the deadline. Additionally, Hill isn't the same kind of ball-dominant player that Walker has been at his best.
As a result, I wouldn't be surprised if Oklahoma City tried to move Walker again this offseason rather than waiting for him to rebuild value. We'll see whether the Thunder can again manage to get paid with a first-round pick on both sides of the transaction.