The Vikings are hoping the 5-foot-9, 180-pound Pro Bowl cornerback can be ready for a big test Sunday in Pittsburgh against the suddenly pass-happy Steelers.
But Winfield has missed the first two days of practice this week, which is not a good sign.
"If there's anybody that has a chance [to play] because of the notes he takes and how he looks at it, [it's Winfield]," coach Brad Childress said Thursday. "At some point you have to warm up and move around, but I don't know right now."
The contrast between the defense with Winfield and without was stark against the Ravens. The Vikings forced Baltimore to punt on its first five possessions as they jumped out to a 14-0 lead. One of the league's best tackling cornerbacks held the edge against Baltimore's running backs and kept receivers Derrick Mason and Mark Clayton under wraps.
But he went down in the second quarter, and Joe Flacco started to pick apart the secondary from then on out.
"I don't think you can [compensate] for a guy like Antoine with some of the things he does," defensive tackle Kevin Williams said. "He's so physical. You very seldom see corners like that, who are that physical in the run game. He plays a big part when we're in our Cover 2 defense. Those guys know they're role and they'll step up and help us out with that."
Flacco went right at backup Karl Paymah, who played almost exclusively on special teams in the first five games of the season. Paymah was beaten throughout the second half, particularly when Flacco threw for 196 yards and two touchdowns in a 21-point final period.
One of the most glaring plays was a 63-yard catch-and-run by running back Ray Rice to Winfield's side of the field.
"You don't think that's going to happen if he's out there," defensive coordinator Leslie Frazier said.
The Vikings (6-0) held on for the 33-31 win when Steve Hauschka's 44-yard field was wide left at the final whistle.
"It was a tough position to put any corner in last week," linebacker Ben Leber said. "Backups get marginal reps during the week and to ask these guys to come in and play at a high level is a tough thing to do. No doubt they have to do it. This is our first real test with [Winfield] not being in the lineup so it still remains to be seen."
Childress said they will evaluate Winfield throughout the week, hoping to make a decision on his playing status by Sunday. But Leber wasn't the only player speaking as if they would be without one of their leaders against the physical Steelers offense.
"When one guy goes down, the next guy stands up," cornerback Cedric Griffin said. "We have talented guys here on our team. All of our games just have to elevate and just replace Antoine."
The timing is difficult for the Vikings, who are off to their best start since 2003.
The Steelers (4-2) have morphed from a power-running team into a wide-open, shotgun attack. Ben Roethlisberger has attempted at least 30 passes in all six games and threw for 417 yards last week against Cleveland. Receiver Hines Ward leads the league in receiving and Santonio Holmes and tight end Heath Miller give the Steelers a balanced aerial offense.
It remains to be seen what the Vikings will do if Winfield cannot play. Paymah could get the start, or nickel back Benny Sapp could slide to the outside to take Winfield's place. Asher Allen, a third-round pick out of Georgia, is a candidate to be activated for the first time in his career.
"We all have confidence in myself, Karl Paymah, Benny, Asher," Griffin said. "We'll get the job done.
Allen has been practicing both on the outside and covering the slot in the team's nickel package.
"I played corner my whole career in college. I played in the SEC and went against talented receivers that are in the NFL now," Allen said. "Also played nickel. If coach wants to put me outside, he can do that, if when wants to put me inside, just whatever's best for the team I'll be doing it."