METAIRIE, La. — If Michael Thomas isn’t careful, he might run out of ammunition soon.

The New Orleans Saints receiver is fueled by doubters. He’s propelled by an intense passion built up through a lifetime of being a late bloomer in high school, struggling early to get on the field at Ohio State and falling to the second round of the 2016 draft.

His teammates and coaches marvel at an almost maniacal drive that never lets up. Quarterback Drew Brees talks about how Thomas treats every rep in practice like a “Super Bowl rep.” Coach Sean Payton recently told NFL.com that he felt like he got hit by a car when he made the mistake of standing in as the defensive back across from Thomas during a walk-through session.

But if he keeps living up to his nickname, “Can’t Guard Mike” is going to run out of doubters soon.

Thomas was named a first-team All-Pro in his third NFL season after setting franchise records with 125 catches and 1,405 yards to go with nine touchdown grabs. And now he’s got another chance to flex on the biggest of stages, as the No. 1-seeded Saints begin their playoff run Sunday against the Philadelphia Eagles (4:40 p.m. ET, Fox) in an NFC divisional-round game.

“The playoff stage is just all about winning,” Thomas said this week, rejecting the question about what it means for him personally. “Whatever it takes to win, be the last team standing, play for a championship and ultimately win a championship is what the playoffs mean to me.

“[This opportunity] is a blessing. It’s what we work for. That’s what training camp, OTAs, all the meetings, all the extra work after [practice], the offseason reps — it’s a testament to the position we’re in now. And we just want to keep it going.”

Thomas, however, has never made any secret about his lofty aspirations to be considered “right there with the best of them” when all is said and done in his career. And we already have seen glimpses of how he thrives on the biggest stages.

You might remember Thomas catching the game-clinching, 72-yard touchdown in the Saints’ most high-profile showdown of this season against the Los Angeles Rams — then pulling a cellphone out from under the goal post because he had prepared ahead of time for having such a big moment in the spotlight.

Last season’s playoffs were no different.

Thomas caught eight passes for 131 yards in the Saints’ wild-card victory against Carolina. Then he caught seven passes for 85 yards and two scores in the divisional-round loss at Minnesota. Both of Thomas’ touchdowns came in the second half as New Orleans rallied from a 17-0 deficit — even though he was being guarded by All-Pro cornerback Xavier Rhodes.

Brees has had some great pass-catchers in his 13 years with the Saints — including Marques Colston and Jimmy Graham. But Thomas has emerged more than any of them as someone Brees will target in those gotta-have-it moments, even when he’s being swarmed by No. 1 cornerbacks and double-teams — in part because of the lack of proven depth the Saints have in the rest of their receiving corps.

“Listen, you make good, wise decisions, smart decisions. [But] if he’s one-on-one, I like our odds. Even when he’s 2-on-1, it better be a really good 2-on-1 or else there’s usually still a place you can throw the ball where he can get it and they can’t,” said Brees, who called Thomas’ astounding total of 125 catches “pretty awesome.”

“That says a lot about him, because obviously he gets a lot of attention. It’s not like they just put him on an island every game. He’s getting a lot of double coverage. He’s getting a lot of safeties leaning his way and different things. So, he’s gotta work hard to get open and he does. He does a great job of that.

“He’s highly competitive. He expects to be the guy to get the ball and make the big play, so that’s great. It also opens up opportunities for other guys.”

Payton quickly rejected the notion the Saints would ever target Thomas no matter how heavily he’s being covered: “No, no, no, no, no, no. No. … We don’t just drop back and throw the ball indiscriminately to a player.”

But, Payton said, “Our job during the week is to try and figure out how to take the double-team off of him or how to slow that down.”

Even though he’s still a young player in the NFL, the 25-year-old Thomas said he takes his responsibility seriously as Brees’ go-to target.

“Being there, being his guy, having the most experience with him, I have to act like I have the most experience with him,” Thomas said. “I can’t leave him out there.”

Thomas also probably has to deal with as much physical contact as any receiver in the league, both because of his “go-to guy status” and because he spends a lot of time playing in traffic as a physical 6-foot-3, 212-pounder. And he can’t help but vent sometimes after games when he feels the officials let defensive backs get away with too much grabbing against him (the Saints’ 13-10 loss at Dallas in Week 13 among them).

But he also knows that’s a reality he has to live with since opposing defenses certainly don’t underestimate him.

“I had to fight — I definitely had to fight for it,” was Thomas’ first response when asked about the numbers he put up this season. “But that’s just the numbers that I turned in at the end of this year.

“I’m ultimately trying to turn in better numbers next year and try to take that next step in my game. I’m not trying to pat myself on the back or say, ‘Good job.’ I’m just trying to ultimately be the last team standing and help my team win a championship.”