SAN FRANCISCO — The Celtics are certainly a different club this year, and that goes beyond the roster.

In the midst of discussing Kemba Walker prior to the Celtics’ 105-100 win over Golden State on Friday, Warriors Coach Steve Kerr dropped in a line that sort of captured the change in the Boston vibe.

Kerr, an assistant coach on Team USA, said of Walker, “I was with him this summer in China for the (FIBA) World Cup.  … I had no doubt while I was coaching him this summer that he’d be great for the Celtics, given not only his ability on the court but the chemistry he generates with a group. Everybody loves playing with him, he moves the ball, he plays hard, he’s fun to be around.

“You could tell over the summer that those guys would click, and they absolutely have. They’ve gotten off to a great start.”

Walker did not get off to a great start against the Warriors on Friday, shooting 1 for 11 to start.

Then he hit 5 of 8 shots he took in the final 8:26 of the game to score 14 points – basically half of Boston’s total output in the fourth – and finished with 20.

NETS: Guard Kyrie Irving missed Brooklyn’s game at Chicago because of a shoulder injury.

The team made the announcement before the game on Saturday night.

Irving had 17 points and nine assists at Denver on Thursday after being listed as questionable before the game.

WARRIORS: Golden State guard D’Angelo Russell will be sidelined for at least two weeks after he sprained his right thumb Friday against the Celtics, further depleting the backcourt already missing injured Splash Brothers Stephen Curry and Klay Thompson.

The Warriors said Russell received an MRI exam after the game that revealed the sprain and he will be re-evaluated in two weeks. Russell wasn’t going on the team’s four-game road trip that begins Sunday at New Orleans that also includes stops in Memphis, Dallas as Utah.