The reigning NBA champion Boston Celtics have kept pretty much everything the same all summer. There was no reason to make any major changes after winning 64 games and overwhelming their opponents in the NBA playoffs.

But even teams with incredible roster depth are looking to add more as the season quickly approaches.

Boston did just that on Wednesday, signing former first-round pick Lonnie Walker to a one-year deal for the guard, according to ESPN’s Adrian Wojnarowski.

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That’s a pretty good catch for the defending champions. Walker, 25, was a first-round pick of the San Antonio Spurs from Miami (F) in 2018.

He spent four seasons in San Antonio, averaging 9.4 points on just 41% shooting from the field, but the guard has improved since then.

Last season with the Brooklyn Nets was Walker’s best, averaging 9.7 points and shooting a solid 38% three-point percentage.

Walker will fill one of the final roster spots for Boston, backing up both Derrick White at the two and reigning NBA Finals MVP Jaylen Brown at the three.