SAN ANTONIO -- Spurs guard Danny Green, who already was a scratch for Friday night's preseason finale against Houston, will be sidelined for three weeks with a strain of his left quad, coach Gregg Popovich said Friday night.

Popopich said the injury is the same one he sustained playing pick-up ball before the start of training camp.

He missed the first eight days of camp with the injury. He played in Tuesday night's Silver and Black scrimmage, but aggravated the injury and went to the bench in the second half.

"It's the same injury," Popovich said.

The Spurs sent out a release saying that Green, one of the team's best perimeter defenders, will be out "approximately" three weeks. Kyle Anderson, who is preparing for his fourth season with San Antonio, will start in Green's place when the Silver and Black host Rockets in their last preseason game.

Forward Jonathon Simmons has a right-calf contusion and also will miss Friday night's game, but Popovich said he "probably" will be back in a few days probably just a few days, maybe.

"Danny will be weeks," Popovich said.

The club simultaneously sent out the release saying Green has been diagnosed with a left-squad strain. His absence will leave the Spurs without one of their best-two plays when they open the regular season against two-time defending Western Conference champion Golden State next Tuesday in Oakland, Calif.

Earlier Friday, the Spurs announced that they have exercised their fourth-year option on Anderson for the 2017-18 season. A UCLA alum, Anderson was selected by the Spurs in the first round of the 2014 NBA draft with the 30th overall pick.

"Mostly confidence," Popovich said, when asked in what areas Anderson has improved since his rookie season. "He was always able to pass the ball and he's got a good feel for the game. His shot has gotten better and his confidence level has risen with the playing time that he got last year. He's just a good, solid player."

Anderson, who started 11 games last season averaged 4.5 points, 3.1 rebounds and 1.6 assists in 16.0 minutes over 78 games.

In another matter, Popovich was asked if he had spoken with forward LaMarcus Aldridge about the rumors that surfaced earlier this week that the Spurs were open to trading him sometime this season.

"There's always rumors. You guys are always writing something," Popovich said. "I'd spend half my time talking to players about the s--- you guys write. What would I do then?"