"There's definitely a hole with Klay not being there," Kerr said Tuesday, per Colin Ward-Henninger of CBS Sports. "There's a hole in the lineup and there's a hole in our hearts, just because he's such a huge part of who we are."
It will be the second straight missed season for Thompson, who didn't play in 2019-20 while recovering from a torn ACL. The team struggled to a 15-50 record last year—worst in the NBA—but will at least return Stephon Curry after getting just five games out of the two-time MVP.
A healthy Draymond Green adds a second key part of the team's core, although Kerr said he believes there are "probably" four spots already set in the starting lineup with Kelly Oubre Jr. and Andrew Wiggins also playing.
"I mean, it would be hard for me to not see Kelly and Andrew starting on the wings," the coach said, per Anthony Slater of The Athletic.
Oubre has gone from the Washington Wizards to the Phoenix Suns to the Warriors over the past few seasons (plus a few days with the Oklahoma City Thunder), but he could have a significant role with his new team thanks to his defensive ability.
"(Wizards coach) Scott (Brooks) told me that he felt like Kelly was at his best on the ball," Kerr said. "He's got a toughness about him. I envision us using Kelly quite a bit on the ball."
With Oubre and Wiggins both listed at 6'7", the team's length on the perimeter could cause problems for opposing teams.
It leaves only the center spot up for grabs entering training camp, with No. 2 overall draft pick James Wiseman likely playing a significant role. Kerr showed his excitement for the player's potential but wants to temper expectations:
"James' potential athletically is so dramatic that he'll have a chance to step in and help us because he's so athletic and dynamic. But there's a ton to learn and he doesn't have the value of a summer league and a summer of workouts. A lot to catch up on. I'm excited for James, but also want to preach caution for everybody not to expect too much too soon. He played three college games. He has a lot of things to learn."
Kevon Looney could begin the season starting at the 5 thanks to his experience, while Marquese Chriss is another option for Golden State.