Either the Ravens (4-4) will halt a losing slide that has all but ruined their playoff outlook with a victory today over the Cincinnati Bengals (2-6) at M&T Bank Stadium, or they will be relegated to a largely irrelevant second half of the season with pride and job security the primary remaining stakes.
And McNair, a four-time Pro Bowl passer who has struggled so mightily that he's facing a growing chorus yelling for him to be benched and replaced by once-ridiculed former starter Kyle Boller, sorely needs to reverse his bumbles under center.
It's put-up or shut-up time for the reigning AFC North champions, especially since they are expected to field their original starting lineup for the first time since opening the season with six turnovers in a 27-20 road loss to the Bengals.
Factor in that the Bengals field the NFL's No. 31 defense and are tied with the winless Miami Dolphins for most points allowed in the league, and there's little doubt about what needs to transpire today.
"We just have to go out there mainly with the mind frame that everybody is against us right now," said McNair, who has committed eight turnovers this season in the form of three interceptions and five lost fumbles. "Right now, we as a whole, as a team, know we're all by ourselves. And that's a good thing, because once your back is against the wall you have to come out fighting. That's what we're going to do Sunday."
McNair is coming off one of his worst games in his 13-year career during last week's loss to the Pittsburgh Steelers.
He completed 13 passes for 63 yards, the lowest passing total ever for an NFL quarterback with that many completions. And he fumbled twice, was intercepted once and sacked five times.
It was the second lowest passing total in Ravens history behind Scott Mitchell's 48-yard output prior to him being benched permanently by Ravens coach Brian Billick in 1999.
As the Ravens try to stop a two-game losing streak against a Bengals team that hasn't won its past six road games, questions abound on whether McNair is facing a quick hook from Billick.
Although Billick has reiterated that McNair remains his starter and hasn't awarded more snaps in practice to Boller, he hasn't ruled out benching the former NFL Co-Most Valuable Player.
The Ravens rank 24th in passing. And with McNair in the lineup, they have produced just 58 points. His turnovers have led to 45 points by opponents.
His last touchdown pass -- he has two for the season -- was against the Cleveland Browns in a September loss.
"You do whatever you have to do to win the game," Billick said. "If you have an option at a position where you think you can do something, no matter what the position, sure. But I don't anticipate that happening. I think Steve's going to play well."
"It would have to be a dramatic circumstance. We've got a lot of faith in Kyle, but we have great faith in Steve McNair that he's going to do the things that he's done for us before."
Billick was probably referring to last season, not this injury-plagued one where McNair, 34, has appeared to be in slow motion due to either his age or back and groin injuries.
Last year, McNair passed for 3,050 yards and 15 touchdowns. However, his past seven starts have produced two scores and six interceptions.
Meanwhile, the Bengals' secondary looks extremely exploitable, rivaling the shorthanded Ravens' defense.
The Bengals are allowing 397 yards per contest, surrendering 30.5 points per game.
If McNair can't turn it around against Cincinnati, it begs the question: When can he?
"It's an opportunity for us to go out there and prove everybody wrong, especially on the offensive side of the ball," McNair said. "What better day to go out there at home and fight hard and play hard?
Something positive needs to happen soon, though.
Especially since the Ravens' toughest remaining games are ahead of them against the undefeated New England Patriots and the defending Super Bowl champion Indianapolis Colts.
"I'm still smiling, I still see the glass as half-full, not half-empty," wide receiver Derrick Mason said. "We still have a long season to go. A lot of people have already written us off. Pittsburgh has written us off, judging from what was said.
"We can still finish this thing at 12-4. We have to think that way. We can't let the outside circumstances determine what we can do in this locker room. We'll continue to have a smile on our face. We'll work through this."
The Bengals are equally determined. There have been loud whispers about coach Marvin Lewis' head being on the chopping block.
His defense is putrid with quarterbacks producing a combined 101.2 rating against them.
They rank 32nd in yards per pass play, 30th in rushing yards per attempt, 29th in first downs allowed and 28th in passing yards allowed.
"Unlike the great season we've had?" Billick quipped. "Both teams are desperate for a win. That makes us both very dangerous."
The Bengals' great equalizer is Pro Bowl quarterback Carson Palmer and a gifted receiving corps that features T.J. Houshmandzadeh, Chad Johnson and Chris Henry in his first game back since serving an eight-game suspension for violating the NFL's personal conduct policy.
Palmer has thrown 12 career touchdown passes against Baltimore with Cincinnati winning five of the six past meetings and two of the last three games in Baltimore.
And Palmer has to be licking his chops at the prospects of firing deep passes against a secondary that could be missing anywhere from one to three starters today with cornerback Samari Rolle (illness) already ruled out and cornerback Chris McAlister (knee) and safety Ed Reed (concussion, neck) regarded as game-time decisions.
The Ravens allowed five touchdown passes in Monday night's 38-7 rout to the Steelers.
A similar game plan is likely in the offing from the Bengals.
"I don't think it was a meltdown," linebacker Terrell Suggs said. "I think they did what any professional team would do. They knew we didn't have our two starting corners.
"That's what I would have done. I would have thrown the ball every play, if you ask me. They played a really good game and we played a really bad one."
The Ravens can't afford to have another bad one today, though.
Not after losing to all three division opponents already by a combined margin of 52 points.
"Payback, definitely," Suggs said. "I think it's a Japanese proverb that said, 'Revenge is a dish best served cold.'"
Aaron Wilson covers the Baltimore Ravens for the Carroll County Times and the Annapolis Capital.
Lot on the line for Ravens, McNair
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