Mackenzy Bernadeau kept trying to convince himself of that in his first week of training camp with the Carolina Panthers last summer. That’s when the former standout offensive tackle from Division 2 Bentley, who was selected in the seventh round (250th overall) of the 2008 draft, found himself going head to head against Julius Peppers, a four-time Pro Bowl defensive end.

“Yeah, at first it was a little bit of a shock when I went up against Julius Peppers,’’ Bernadeau said yesterday by phone from Charlotte, N.C. “At the same time, he was just an opponent I was going up against, one on one. He’s still going to be the man I’m blocking, whether it’s Julius Peppers or whether it’s Vince Wilfork, I figure I’m going to end up run-blocking them or pass-blocking them. So, after a while, when it’s over, you realize you just got to play the game.’’

Still, that first training camp was a shock for Bernadeau, a 6-foot-4-inch, 320-pounder, who struggled mightily to block everyone he faced.

“It was a complete eye-opener,’’ he said. “Because I realized I wasn’t blocking as good as I was in college and instead of making every play perfect and blocking every play perfectly, I was getting beat more often than I expected. I got down on myself.’’

Once he realized, as his coaches stressed, “That if you’re not getting beat, then you’re not playing,’’ he began to learn from his mistakes.

“In the end, it’s just playing football, no matter who’s across from you,’’ he said. “It’s still just blocking and tackling. In the end, it’s still just football.’’

But tomorrow will be like no other game for Bernadeau, a Waltham native who will make his fourth career start in front of 35 family and friends - with many more expected to watch, including Bentley coach Thom Boerman - when the Patriots host the Panthers at Gillette Stadium.

Bernadeau, who was listed as the backup left guard, found himself thrust into a starting role when left tackle Jordan Gross went down with a season-ending fractured ankle Nov. 15 against the Falcons. When left guard Travelle Wharton was shifted to tackle, Bernadeau filled in at left guard, making his first career start against the Dolphins Nov. 19.

“It’s been the talk of campus,’’ Boerman said of Bernadeau’s homecoming.

“Everyone’s trying to get out there to see the game and watch Mack play. It’s funny, when I watch football games in general, you tend to watch the flow of the game and follow the ball. But I find out when I watch the Panthers, I watch Mack. I watch him on every play and see how he’s doing and he has been playing very well.

“It’s been fun to watch. I’ll be rooting for the Patriots, but I’ll be pulling for Mack to do well on every snap that they have.’’

Boerman won’t be alone in that sentiment. Bernadeau has had many rooting for him since he became the first football player from Bentley to blaze a trail to the NFL. He overcame not only the small-school stereotype, but also a left knee injury that truncated his senior season and caused interest from NFL scouts to wane.

But there were people, such as former Bentley coach Peter Yetten, whose faith in Bernadeau never wavered.

“I know that when Coach Yetten was the head coach here, he was always telling him, ‘Mack, I think you’re going to be an NFL guy,’ but I don’t think Mack really believed it,’’ Boerman said. “I never saw Mack just embrace it and say, ‘Yeah, I’m going to be an NFL guy,’ until about halfway through his junior year when he started to get some scouts coming over here and getting some attention. I think it was then Mack realized, ‘Maybe I am good enough.’

“That’s when he really believed there might be an opportunity for him and he worked that much harder.’’

The Panthers saw a tremendous upside in Bernadeau.

“He had all the physical tools,’’ said coach John Fox. “He just needed some development. He sat around and did some special teams things and sat in those meetings and learned from some veteran guys. And when the Jordan Gross injury occurred . . . we had to make some adjustments and he got plugged in at the guard positions. I saw him, we all had a pretty rough outing offensively versus the Jets [a 17-6 loss Nov. 29 on the road], and I thought he rebounded nicely last week against Tampa Bay.’’

Bernadeau committed himself to making it to the NFL, but he hedged his bet by getting his degree in business management.

“Back then I didn’t want to go around thinking that, ‘I’m making it to the NFL,’ because I knew my chances were slim and the odds were against me, coming from a D2 school,’’ said Bernadeau, whose chances grew even slimmer when he wasn’t invited to the NFL’s scouting combine in Indianapolis.

“I went into it with the mentality that I’m going to try everything I can to make it to the NFL with what I have, despite knowing that if it doesn’t happen, then it’s not the end of the world. So not getting invited to the combine was a little bit of a setback, but I still had my mind set on my goals.

“Every time I reach one goal, I change to another and make another goal. I guess now that I actually realize I’m playing in the NFL, it’s not something I’m in awe of anymore, it’s just more of a dream come true.’’

Michael Vega can be reached at vega@globe.com.