Video (01:25) : Adrian Peterson talked about Sunday's game in Detroit and said going against Lions star receiver Calvin Johnson is something he's excited about because of what they have both accomplished.

Defensive end Everson Griffen returned to practice on Thursday and said there’s no question that he’ll play Sunday in Detroit.

Griffen was a late scratch from last Sunday’s 16-10 win over Kansas City. The Vikings said he was sick, but no further details were provided.

When pressed for details on Thursday, Griffen said “I’m not going to release all my medical information to you. That’s not my job. … That’s private and I’m going to keep it that way. But yeah, I was sick and handled it accordingly. But now I’m back and I’m back with my teammates and I’m feeling healthy and feeling strong. And I’m ready to go out there and beat Detroit.”

Griffen said there’s “100 percent” chance he’ll be back on the field Sunday. He doesn’t expect any residual effects to flare up heading into Week 7.

Griffen said he didn’t feel sick until last Sunday morning and then met with the Vikings training staff. They determined it would be best if he checked into Hennepin County Medical Center and underwent further testing.

He was later released from the hospital and said he caught the end of the game from home.

“I just felt sick. I felt like I wasn’t all the way where I needed to be,” Griffen said. “I’m thankful [it was handled appropriately] because I could have gone out there and gotten injured or something bad could have happened. But I went to Hennepin County and everything checked out right and I’m happy to be back.”

Griffen appeared healthy doing drills on Thursday. Defensive tackle Sharrif Floyd, who missed Wednesday’s practice with an injured knee/ankle, didn’t practice again. Defensive end Justin Trattou (foot) also remains out.