Sports

5-1 Ravens on cusp of a fall

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Rarely has a 5-1 record in the NFL felt so fragile.

The Ravens might be off to a flying start, but there are a lot of ominous signs that Baltimore is headed for crash landing — a tailspin that could start as soon as Sunday in Houston against the Texans.

That’s because it is difficult to remember one of the league’s top teams posting a costlier victory than the one the Ravens posted at home over the Cowboys last week.

Baltimore lost two crucial pieces of its vaunted defense — Ray Lewis and cornerback Lardarius Webb — to what appear to be season-ending injuries in the 31-29 win, while standout nose tackle Haloti Ngata sprained both his MCL and shoulder. And if that wasn’t bad enough, all-world safety Ed Reed admitted during the week that he is playing with a torn labrum.

As a result, the Ravens’ defense is little more than a shell of itself as Baltimore heads to Reliant Stadium. Pass-rush ace Terrell Suggs might make his season debut, but that prospect was little consolation to defensive coordinator Dean Pees this week.

Pees blasted his unit — particularly the run defense — in surprisingly blunt fashion after Dallas rolled up 30 first downs and nearly 500 yards in a losing cause. Baltimore has allowed more than 200 rushing yards in each of its past two games, including 214 to the Chiefs in a 9-6 win two weeks ago.

“It makes me sick, is the best way I can put it,” Pees. “I mean, it really does. I’m as happy as I can be to be 5-1. But I also feel fortunate to be 5-1, the way we’re playing on defense.”

Barring an immediate turnaround by the defense, the Ravens’ injury situation puts the onus on Joe Flacco and a Baltimore offense that is, to put it lightly, inconsistent.

The Ravens mustered just three field goals against lowly Kansas City and struggled to score points last month in a home win over the Browns, yet put up 44 on the Bengals, 31 on the Cowboys and 31 on the Patriots.

So it’s any guess which version of Flacco and the Baltimore offense will show up against J.J. Watt and a Houston defense that no doubt will be angry today after getting uncharacteristically torched at home Monday night by Aaron Rodgers in an embarrassing, 42-24 loss to the Packers — when Rodgers threw a whopping six TD passes.

The Texans also will be determined to end Baltimore’s hex over them. Houston is 0-6 all time against the Ravens, including a playoff loss last season.

PICK: Texans, 28-16.

CONTENDERS

Cardinals (4-2) at Vikings (4-2): It’s a matchup of two of the softest 4-2 records you will ever see at the Metrodome. Arizona has lost two in a row after a 4-0 start, including a home loss to the lowly Bills last week, while the Vikings are coming off a defeat at Washington that showed Christian Ponder still has a ways to go before convincing anyone he is a reliable starter. But the Vikings have Percy Harvin, a dynamic playmaker who is meriting legit NFL MVP consideration at the moment.

PICK: Vikings, 17-10.

Lions (2-3) at Bears (4-1), Monday: Chicago gets another primetime opportunity to prove the resurgence this season is real, as well as put some more distance between itself and the rest of the NFC North. Jay Cutler and Brandon Marshall will get the most attention, but the showdown between Detroit’s NFC-leading offense and the Bears’ stiff, playmaking defense is the more intriguing angle. Chicago also has won seven of the past eight meetings.

PICK: Bears, 30-14.

bhubbuch@nypost.com