The Celtics’ offseason turned toward a full reset on Monday when free agency began. **Luke Kornet** and the Spurs agreed to a four-year, $41 million that ended his five-year tenure with Boston and cast both the center position and the greater Celtics roster outlook into uncertainty.
The Celtics agreed to a two-year, $5.3 million deal with **Luka Garza** to add some depth to the position, though he arrives in Boston with limited NBA playing experience entering his 27-year-old season. Meanwhile, free agent **Al Horford** and the Warriors appeared to have momentum toward agreeing to a deal on Monday, according to multiple reports, before Michael Scotto connected Horford to various suitors, including the Celtics.
If Horford follows Kornet’s lead and departs Boston, the Celtics face a precarious path to rebuilding the center position before **Jayson Tatum** returns later in 2026. **Jaylen Brown**, **Derrick White** and Tatum remain as a compelling core, while salary reducing moves from last week likely allowed the team to retain **Payton Pritchard** and **Sam Hauser** for now. Beyond them, it’s unclear how the Celtics can recapture a championship contending supporting cast, or even find a starting caliber center. Only **Neemias Queta**, **Xavier Tillman Sr.**, Garza and second round pick **Amari Williams** fill the position for Boston at the moment.
Garza played the past three seasons with the Timberwolves organization, mostly in the G-League, following his selection from Iowa as the No. 52 pick to Detroit. He emerged as the best player in college basketball late in his career there, but his defensive limitations and foot speed made him a challenging NBA fit. Still, the Celtics reportedly monitored Garza and inquired about his ability throughout his Minnesota tenure. He averaged more than 30 points per game in his 18 appearances with the Wolves’ G-League affiliate in Iowa. Garza plays a pick-and-pop style at center and can seal smaller defenders with post-ups effectively.
Still, his addition hardly scratched the surface of what Kornet provided in 2025. He emerged as a more regular spot starter for the Celtics who could play in tandem with **Kristaps** **Porzingis** and Horford. The Celtics even considered his presence, which allowed for various double-big lineups, one of their biggest strengths compared to during the championship run. Kornet’s spot start in Game 5 that saved the Celtics’ season briefly at home against the Knicks will go down as his last game at TD Garden — and greatest performance in a Boston uniform.
**Danny Ainge** initially acquired Kornet as a throw-in from Chicago in the **Daniel Theis** salary dump. By then, Kornet battled injuries and shot inconsistently in the pick-and-pop role he entered the NBA playing. That shooting created some staying power upon arrival with the Celtics, who waived **Moe Wagner** instead. Still, Kornet found no NBA offers in free agency that summer and accepted a G-League contract with Maine. He reshaped his game that season between Maine and emergency COVID fill-in contracts with Milwaukee and Cleveland. The Celtics later signed Kornet to a standard contract after acquiring **Derrick White** at the trade deadline. In 2022-23, he found rotation minutes, built on them into 2024 and flourished throughout 2025.
Kornet became a free agent last summer too, but declined a one-year, $7 million contract offer from the Jazz to play for the Celtics on the league minimum. He cited having the chance to attempt a championship repeat with a roster that mostly returned inspired his decision. Kornet did not have that opportunity this time, with the Celtics’ direction already evident from their two offseason trades and a draft night that looked toward the long term. For Kornet, he’ll supplement the Spurs’ front court alongside **Victor Wembanyama** as the Spurs try to pivot toward winning in **Mitch Johnson’s** first full season as head coach and **De’Aaron Fox’** playing in San Antonio since landing there from Sacramento at the trade deadline. Kornet played high school basketball four hours north in Argyle.
The Celtics filled their 13th roster spot with Garza, leaving one left to fill to reach completion ahead of Horford’s decision. Though while **Brad Stevens** expressed hope that Boston could retain Horford and Kornet before the latter’s departure, the Celtics did not agree to another trade that created separation between themselves and the second apron. That remained the case on Monday following the Garza signing, which pulled Boston back within $2-million of that threshold.