"Adrian Peterson was back at practice Thursday. Christian Ponder was not. Where that leaves the Vikings offense heading into Sunday's game in Detroit is anybody's guess.

Both players could be ready for action. Equally possible: Neither Peterson nor Ponder plays against the Lions.

In that regard, Friday's practice will now be a major measuring stick for coach Leslie Frazier as he weighs his options with both players.

Peterson has been out because of a high ankle sprain since the first quarter of the Vikings' Week 11 loss to the Raiders. Thursday marked his first practice since suffering the injury. And Frazier sensed the star running back feeling more comfortable with his cutting.

"He's headed in the right direction," Frazier said. "Far more improved than he was a week ago. So we're encouraged by his work. ... He had trouble before planting and cutting. He was much better doing that today. That was one of our concerns. Because we all know, he's one of those guys who runs hard, and he'll stop on a dime and cut in any direction. He was able to do that today without pain. So that was encouraging."

Ponder, meanwhile, still is limping around after suffering a hip pointer Sunday against Denver. He missed his second consecutive practice Thursday. In his place, Joe Webb has taken all the snaps with the first-team offense this week, in line to start in Detroit if necessary.

Frazier must wait to see if Ponder can practice at least a little Friday.

"If he's not able to do anything [Friday], it'd be hard pressed for us to put him in the game," Frazier said. "We'd need to see him take some snaps and move around a little bit to make a decision about him playing.""