OWINGS MILLS, Md. -- Can we agree on one thing this morning? That the Baltimore Ravens' Ed Reed is a better safety than the Steelers' Troy Polamalu?

Steelers offensive coordinator Bruce Arians said it last season. "I personally think [Reed] is the best. I love Troy, and I think he's good, but Ed is really good."

The Ravens said it here this week. "[Polamalu] is a good player, but he's not Ed Reed," wide receiver Derrick Mason said. "Reed is different. Even when he's not covering, he's covering. Even when he's not in the box, he's in the box. I think there are two of those guys out there, two No. 20s. One in the box and one over the top."

Even the always humble Polamalu has acknowledged Reed's edge.

"I've told Ed that. 'You're the best I've seen.' The best ever, in my opinion." • That makes it pretty unanimous.

Earlier in the week, Baltimore defensive coordinator Rex Ryan called Ravens 10-time Pro Bowl linebacker Ray Lewis "a once-in-a-lifetime guy," then quickly added: "I'm pretty lucky because I have two of 'em. Ed probably will go down as the greatest free safety in the game."

Short term, the Ravens will settle for Reed making one more splash play than the great Polamalu in the AFC championship game tomorrow night.

Says here that's the only way the Ravens will leave Heinz Field with a win and the biggest of prizes, a trip to Tampa for Super Bowl XLIII.

For the first time, the Ravens' defense showed a little vulnerability last weekend in a 13-10 playoff victory at Tennessee. It was gouged for 391 yards. Titans rookie Chris Johnson ran for 72 yards on 11 carries before leaving with an ankle injury in the second quarter.

Maybe the Titans discovered a tactical flaw that Arians and the Steelers offense can exploit. More likely, it was a combination of the Ravens playing their 17th consecutive game without an open week and the fact that star pass rusher Terrell Suggs (shoulder) and top cornerback Samari Rolle (groin) missed most of the second half.

Rolle isn't expected to play against the Steelers, and Suggs should be limited if he plays at all, but the wearisome Ravens still are planning on showing up, darn it.

"I read all the experts say we would have given up 150 yards to the running back from Tennessee," Ryan said, sniffing. "But, remember, he never finished the game for some reason. Whatever the reason, they can cry all they want. Who cares? We're here. We're still playing, and they can watch us."

Rough translation:

Fast Willie Parker and the Steelers are crazy if they think the yards will come easily on the Heinz Field grass …

Certainly, Ryan has reason to be confident in his bunch. It hurts big time losing Rolle and possibly Suggs, but as long as No. 20 is on the field, the Ravens will take their chances.

Reed is that much of a game-changer.

The Ravens still are alive in the NFL postseason tournament because no defense is better than theirs at forcing turnovers. In a win at Miami two weeks ago, they had four interceptions and a fumble recovery against a Dolphins team that had committed just 13 turnovers all season. Last week at Tennessee, they survived and advanced because they came up with two fumbles and an interception, all deep in Ravens territory when the Titans looked as if they were going to score.

"We have a slogan here: 'They're not in 'til they're in,' " Ravens linebacker Bart Scott said.

Added Lewis, "We take pride that we'll give you a little bit, but we're not going to give you everything you are looking for."

The turnovers are nothing new for the Ravens' defense. It led the league with 34 takeaways this season, producing or setting up 123 points for the team. The turnovers also don't happen by accident. Ryan said he doubts any NFL player studies the opposing offense more than Lewis, but, if there is one, it's Reed.

"He's one of the most instinctive players I've ever seen in football," Steelers quarterback Ben Roethlisberger said.

What?

You thought it was a coincidence Reed always seems to be around the ball?

Know this about the man: He's not just a smart player, he's smart, period. He needed just three years to graduate from Miami with a liberal arts degree.

Back on another South Florida field, Reed had two interceptions in the victory against the Dolphins, giving him 11 this season -- 10 in the past eight games -- and 48 for his seven-year career. But just getting his hands on the ball isn't enough for him. He's always looking to score. He took the first interception against the Dolphins 64 yards for a touchdown, giving him four scores this season and 12 in his career.

That's a lot of splash plays.

"The kid's a freak," Suggs said.

The Ravens are happy to follow Reed's lead. They've scored seven defensive touchdowns this season, counting Reed's against the Dolphins.

That's what's most frightening about the Ravens' defense.

It's not that it hasn't allowed a 100-yard rusher in 35 games or that it allowed a league-low four rushing touchdowns this season or that it's done a marvelous job over the years against Parker, holding him to no touchdowns and an average of 43.7 yards in six games. Parker is healthy -- finally -- and sliced through San Diego's defense for 146 yards and two touchdowns Sunday.

It's not even that the Ravens defense led the NFL this season by holding opposing quarterbacks to a 60.6 passer rating. Roethlisberger should not lack for confidence tomorrow night after leading the Steelers on a 12-play, 92-yard drive in a last-minute, 13-9 victory Dec. 14 at Baltimore.

No, what's truly scary about the Ravens' defense is its enviable ability to win a game with one big play.

Note to Big Ben, Fast Willie and the rest:

Beware tomorrow night.

Always beware of No. 20.