NFL teams haven’t seen Johnny Manziel throws footballs in person since he was released by the Browns in March 2016. (Jason Miller/Getty Images)

Johnny Manziel has been trying to show the NFL that he’s a much more reliable person, one dedicated to his craft and no longer the problem child who partied his way out of the league. However, he also wants everyone to know that he’s still the same talented quarterback who won a Heisman Trophy before becoming a first-round pick, and to that end, he showed off his arm to 13 NFL teams in a workout Thursday.

The audition took place at the University of San Diego, near a private academy run by quarterback coach George Whitfield Jr., with whom Manziel has been training. The university held its pro day for NFL scouts Thursday, but according to ESPN, Toreros wide receiver Justin Priest and tight end Ross Dwelley did not have a quarterback to throw to them, so they invited Manziel, who had tossed passes to them previously.

The occasion marked the first time NFL teams had seen Manziel throw passes in person since he was released by the Browns in March 2016, following two seasons marked by inconsistent results on the field and immature behavior off it. For the 25-year-old, it was another step in what he has been calling “ComebackSZN,” and he described the day as a “good” one.

During the NFL’s draft combine last month, Manziel was reported to be “in touch with multiple NFL head coaches” about possibly returning to the league, and he said at the time he’d play “for free” just to get another chance. Among those reportedly in attendance Thursday were representatives from the Browns, in addition to the Bears, Buccaneers, Chargers, Chiefs, Giants, Jaguars, Jets, Lions, Panthers, Patriots, Raiders and Titans.

Presumably, those teams had an interest — possibly a primary one — in the San Diego receivers, as well, but there’s little doubt they were using the opportunity to take a good look at Manziel. He reiterated to ESPN that his partying lifestyle is behind him, and he is now focused on becoming a better quarterback.

“I drive down here [to San Diego] a couple times a week and work out six days a week, and that’s pretty much the schedule,” said Manziel, who lives in Los Angeles. “I’m a married man. I’m at home with my wife and my dogs, and I don’t have a lot of time after that after doing six-hour training days.

“I’m happy with where things are. I think things are going well, and I couldn’t ask for a better place to be in my life right now.”

“It was good,” Dwelley said of the workout. “[Manziel] spins a good ball. He saw it as a good opportunity to get his foot back in the door, so he was all over it. So it was a good opportunity for both parties.”

“I’m sure there’s a lot of questions — rightfully so — about him. Where he is, what is his level of dedication — and can he even throw the ball? ‘Do you even play, bro?’ ” Whitfield said with a laugh. “So he’s been working and training.”

Manziel is set to work out with Whitfield for another week before heading off to Austin, about a two-hour drive from College Station, Tex., where he starred for Texas A&M. In Austin, Manziel will participate in the two-week Spring League, a showcase for football players looking to latch on somewhere.

The Hamilton Tiger-Cats hold Manziel’s rights in the CFL, and he has been negotiating with that team about a possible contract. It remains to be seen if he plays in Canada, but he clearly would love another shot at the NFL, even if he understands that his track record has caused teams to be wary of him.

“I know I’ve rubbed people the wrong way,” Manziel told ESPN. “I know there’s still people that still doubt what I’m doing and still doubt where I’m at.

“For me, [I have] spurts in the past of being good. I’ve [had] spurts in the past of showing promise and looking like I’m on the right path, and when I think I get there, something else happens. That’s kind of the pattern that’s been there in the last couple years of my life since college. So for me, the key right now is to be consistent and to continue what I’m doing day in and day out.”

Read more from The Post:

2018 NFL Mock Draft: Giants trade down with Bills, still get a QB

With NFL draft approaching, Giants’ trade of Jason Pierre-Paul could be foreshadowing

Despite guaranteed deal, Kirk Cousins likely didn’t set new precedent for NFL free agents

Stephen Curry-linked group drops out as Carolina Panthers’ price reportedly hits $2.5 billion