4:06 PM ET

On the verge of returning from a tornACL in his right knee, San Francisco 49ers defensive back Jason Verrett's latest comeback attempt came to a halt.

That's because Verrett, who had been activated from the physically unable to perform list in October, was injured in Wednesday's practice. The Niners said on Thursday that Verrett will be out for the rest of the season.

Within hours of Verrett's injury, Niners coach Kyle Shanahan expressed optimism that Verrett would be active for the first time this season.

"We considered him last week or two weeks ago, I thought he was close," he said. He was here a lot when we were gone. I expect him to be further along this week since he did some things on his own. I'm going to see him in about an hour.

Since entering the league as a first-round pick of the Bolts, Verrett has suffered a number of injuries. He played just six games in a four-season span because of injuries, including a torn left knee in 2016 with the Bolts and a torn right knee in the same year with the 49ers.