METAIRIE, La. (AP) — Drew Brees walked around the New Orleans Saints’ headquarters on Monday wearing a long-sleeve crew neck shirt that had a small white football and the expression ‘‘Life is good’’ printed on the front.

It was a curious wardrobe choice coming so soon after the New Orleans Saints’ pursuit of perfection was derailed by the Dallas Cowboys last weekend.

‘‘It brings it all into perspective, doesn’t it?’’ Brees said.

Indeed, when a team is 13-1 and one victory shy of wrapping up the franchise’s first ever No. 1 NFC playoff seeding, it’s hard to be too upset over that lone loss for long.

Brees even suggested that while the opportunity for an unbeaten season was important to him and his teammates, there could be some good that comes out of their first loss since 2008.

‘‘What we all realize is that all the things that we’ve not been our best at kind of have caught up to us now,’’ Brees said. ‘‘Winning seems to cover a lot of things up.

‘‘When you lose, that’s when you really realize, hey, this stuff will get you beat unless you fix it. So I’m not a believer in psychological victories, necessarily, by taking a loss. But they do uncover things that maybe you would not have recognized or would not have been able to fix unless that had happened to you.’’

Brees has become an inspiring force for both his team and the rebuilding city where he plays, in large part because of his ability to see — and realize — the opportunity that may exist in every setback.

After all, this is a player who was released by San Diego, with his career in doubt, after a serious throwing shoulder injury at the end of the 2005 season. If that was the nadir of his pro career, it also was the catalyst for his move to New Orleans, where he’s has been such a smashing success that fans have lightheartedly compared him to a savior by giving him the nickname, Breesus.

‘‘It’s disappointing just knowing how close we game, you know, three games left in the regular season to being 16-0 … but the fact is, we’re still very much in position to achieve our ultimate goals,’’ Brees said.

‘‘The goal of going 16-0 or winning every game was not on our goal sheet as a team,’’ Brees continued. ‘‘A division championship was, a first-round bye was, the first seed was and a world championship is, and so all those things are still very much in front of us.’’

Because Minnesota (11-3) lost Sunday night at Carolina, the Saints will finish with the top seed in the NFC with one more win or one more Vikings loss.

This week, the Saints host Tampa Bay, a team coming off only its second victory of the season, and which lost at home to New Orleans 38-7 in Week 11. The Saints will be heavily favored, but nothing has been easy for them lately.

After winning nine of their first 11 games by double digits, the Saints’ last three game have come down to the wire and exposed some troubling trends on both sides of the ball.

The Saints’ scoring totals and total yardage have steadily dropped during the past three weeks. The 17 points they scored against Dallas was the lowest of the season and second-lowest since the beginning of the 2008 season.

The Saints’ offense has been less balanced because New Orleans has been falling behind. They have not rushed 100 yards as a team in three games, managing only 55 at Washington and 65 against Dallas. The Saints’ defense, meanwhile, has allowed three straight quarterbacks to throw for more than 300 yards.

Still, head coach Sean Payton cautioned against seeing the loss to Dallas as part of a three-game trend of declining performances.

‘‘It’s a different team, a different game, a loss. The other games were wins,’’ Payton said. ‘‘I don’t think you’re going to win in this league by 14 or 21 points. I think it’s unrealistic. You do want to pay attention to what you’re doing well and what you’re not doing well and there’s some things we have to get better at.

‘‘Each week, you kind of turn the page to the next challenge, being very careful to pay attention to what just took place,’’ Payton said. ‘‘We’ll continue to do that.’’

NOTES: Payton did not provide any updates on the apparent right leg injury that sidelined Reggie Bush for most of Saturday night’s game, but confirmed that Randall Gay left the game because of a hard hit to the head. … Cornerback Jabari Greer said his comeback from sports hernia surgery is ahead of schedule and that he would like to play this weekend if coaches would let him. Payton has said the regular season finale at Carolina is a more realistic target for Greer’s return.