Vikings' Sharrif Floyd underwent surgery Thursday on right knee

Another knee surgery was needed for Vikings defensive tackle Sharrif Floyd.

Floyd underwent a cleanup on his right knee Thursday, according to head coach Mike Zimmer. When asked if it was another cartilage issue, for which he underwent an operation on his left knee in October, Zimmer nodded yes.

Zimmer said he didn't know how long Floyd would be sidelined. Floyd missed most of four games last year following his midseason cleanup of his left knee.

Floyd hasn't practiced since he played 23 snaps in the Vikings' season opener in Tennessee. He'd been limited throughout the preseason with knee problems, often wearing a brace on his left knee.

"We feel good about the guys we have. He's played, what, 12 plays this year? He hasn't played," Zimmer said. "Kind of out of sight out of mind."

It's another setback for the 2013 first-round pick. Floyd has now undergone at least one cleanup to each knee in the past year.

The Vikings exercised Floyd's fifth-year option this spring, so he's currently under contract through the 2017 season. Though the front office has often signed players to contract extensions the summer before their contract year, meaning Floyd could've earned himself a long-term deal with his play this season.

Floyd is the third Vikings player to undergo knee surgery this month, joining quarterback Teddy Bridgewater and running back Adrian Peterson, who also had his operation on Thursday to repair a torn lateral meniscus.

In other injury news, defensive end Danielle Hunter (knee), linebacker Eric Kendricks (ankle) and tight end Kyle Rudolph (groin) were bumped up to full participation in Thursday's practice. All three were limited on Wednesday. Running back Jerick McKinnon (toe) and fullback Zach Line (neck) were also full participants.

Still limited for the Vikings on Thursday were cornerback Xavier Rhodes (knee) and tight end MyCole Pruitt (knee).