Vikings coach Mike Zimmer said Thursday he still isn't sure if Anthony Barr will be available when the Vikings open the preseason in the Hall of Fame game against Pittsburgh Sunday night.
ESPN's Ben Goessling reports that Barr is dealing with inflammation in his knee.
Barr underwent surgery to repair a slight meniscus tear last season. He missed most of the Vikings' offseason workouts with what Zimmer said was a different injury, and got off to a slow start in training camp.
Goessling notes that the Vikings have had to back him off this week.
Zimmer doesn't appear to be concerned the injury will linger into the regular season – saying the team hopes to have Barr back pretty quickly.
In 12 games last season, Barr was a big part of the Vikings defense. He finished with 70 tackles, four sacks and three fumble recoveries – including one that he returned for a touchdown to beat Tampa Bay.
Barr also spoke to reporters on Thursday. He told 1500 ESPN that he is day-to-day with the injury.
"I'm just a little frustrated, I wish everything was smooth," Barr told reporters. "But things like this you've got to be patient. There's a long time before things get serious, and I just want to make sure when that times come I'll be ready."
Barr did take some reps on Sunday, but sat out practice on Monday and Tuesday and was out again on Thursday.
The Vikings don't open the regular season until Sept. 14 in San Francisco.