The New Orleans Saints defense hasn't quite exhibited leaps-and-bounds improvement since Dennis Allen took over as defensive coordinator three games ago.

But incremental progress still charts as progress and the defense undeniably has taken positive strides, culminating in its best performance of the season against Tampa Bay, when it allowed season lows in points (17), yards (291) and net passing yards (176) in a 24-17 victory.

Entering its nationally televised, Monday night game against Detroit in the Mercedes-Benz Superdome, New Orleans (5-8) still allows the most points per game (30.5) in the league, and has moved from last to next-to-last overall in yards allowed (414.8). But since the change from Rob Ryan to Allen, the defense has allowed 27.3 points and 383 yards per game, down from 31.5 and 424.3 through the first 10 games.

And 41 of those points, and 497 of the yards, were surrendered in a three-point loss to undefeated Carolina.

"The challenge last week was the running game and then the receiving threats," Coach Sean Payton said, referring to Tampa Bay's offense. "I felt like we had a really good plan going in. (Cornerback) Delvin Breaux is playing amazing football. If you really charted his production as a corner the last month, he's been fantastic. I thought we were able to get off the field on third down.

"I do think the (defensive) communication has been streamlined. I said after the game, I felt like, man, there's just been a noticeable amount of fewer misalignments. Half the battle is getting the personnel on the field you want and then getting the defense communicated, and get aligned to it. As easy as that sounds, there's a challenge to it.

"I know it hadn't been good because we haven't won a lot of games. But I would say this past week against Tampa, we did a lot of things well. And against a team that has that balance that concerns you – the running game, with the ability with the two receivers and the tight end to get the ball down the field. I thought we were able to keep the ball in front of us, defend those over the top plays. Tackling, I thought was good, (and) it's going to be at a premium Monday night."

Statistically, the Lions (4-9) appear to be an inviting opponent. Detroit scores 20.5 points per game (23rd in the league) and produces 340.8 yards (22nd), including just 79.3 rushing (last).

Not so, Payton said.

"It's a team that plays a little bit more in space offensively, out of a three-wide set – (receivers) Calvin (Johnson), (Golden) Tate, Lance (Moore), the tight end," Payton said. "Pick two or three of the running backs, all of them are explosive in the passing game.

"So you're going from one team (Tampa Bay) that was a little bit more tight end-fullback condensed formations on first and second down, to a team that's going to be spread out more. The ability to play in space is going to be important."

Improving in that area will be another positive step that the Saints have made defensively under Allen.

"There's been some changes with regard to fronts and coverages that we want to play a little bit more frequently," Payton said. "Any time there's a change like that, there's going to be a noticeable difference in certain things that we want to do. We've gotten the practice work at it and the meeting time at it. We changed a little bit of the way we're installing it.

"I would say that I think the players have responded and yet, there's still a handful of things that we want to improve on. Having (linebacker) Dannell Ellerbe back (after missing five games with a hip injury) was significant for us. He's someone that's a run-and-hit player, he's smart and he brings something to the defense."