NEW ORLEANS — The moment of truth came 10 minutes into Sunday’s important divisional game for the much-maligned New Orleans Saints defense.

Facing a fourth-and-1 at the Saints’ 29, Tampa Bay coach Raheem Morris bypassed a chance to grab a 3-0 lead in favor of handing the ball to second-year running back LeGarrette Blount and moving the chains.

Seemed like a sound decision at the time, considering the the Saints defense entered the game as the league’s 32nd-ranked unit in yards per rushing attempt (5.5).

“They gave the ball to their best running back, and they ran their best power running play,’’ said Jonathan Casillas, who started at middle linebacker for injured Saints’ starter Jonathan Vilma, out with an injured left knee.

“That’s what they do. That’s their modus operandi. They want to run the ball. They have a great tailback. They have a great run-blocking O-line and they wanted to rub it in our face.’’

Thanks to the collective effort of Casillas, strong safety Roman Harper and defensive tackle Shaun Rogers, the Saints stopped Blount shy of the first down and took the ball over on downs at the New Orleans 34.

Five plays later, quarterback Drew Brees connected with wide receiver Lance Moore on a 3-yard touchdown pass and the NFC South-leading Saints never looked back, winning 27-16 before a sellout crowd of 73,043 at the Mercedes-Benz Superdome.

The victory avenged a 26-20 loss to the upstart Buccaneers (4-4) three weeks ago at Raymond James Stadium in Tampa, Fla., and gets the Saints (6-3) back in a positive frame of mind heading into next Sunday’s critical division clash against the Atlanta Falcons (5-3) at the Georgia Dome.

“We felt that in order to win ,we had to get a lot of hats to the ball,’’ Saints coach Sean Payton said. “I thought today, defensively, we stopped the run and forced someone to become one-dimensional instead of us.’’

The Saints’ run defense gained a measure of respect Sunday, limiting the Buccaneers to 84 rushing yards on 24 carries, with 27 coming on a busted run by Blount in the third quarter.

Blount finished with 72 yards on 13 attempts, 87 yards fewer than Rams running back Steven Jackson when he fueled a 31-21 upset victory in Week 8 against the Saints in St. Louis.

That loss prompted Payton to proclaim Sunday’s clash against the Buccaneers as a “bat game.’’ In other words, Payton wanted his team to “lay the wood’’ to the Buccaneers by playing tough, aggressive football for a full 60 minutes.

It is the first such designation by Payton for a divisional game during his celebrated six-year tenure.

“I don’t want to say it’s the turning point in our season, but it’s a huge thing to go 6-3 instead of 5-4,” Saints weakside linebacker Scott Shanle said. “The coaches showed us the stats of teams that go 6-3 have a 70 percent chance of making the playoffs and teams that go 5-4 have a 50 percent chance of making the playoffs. So, there was a lot riding on this game.’’

Shanle perhaps summed it up best.

“We know we hadn’t played well in short-yardage situations all year and getting off the field on third down,’’ Shanle said. “So, we had a situation early on today to exorcise that demon, after talking about it and hearing about it all week.

“That stop on fourth-and-1 in the first quarter set the tone for the whole game. It told them, ‘Hey, we’re here to play some defense today. Third-and-1, fourth-and-1, it doesn’t matter, you’re not going to run the ball on us.’’