He followed that with a high-profile offseason of road trips to Las Vegas and the NBA Finals. Manziel got to meet Heat star LeBron James and rapper Drake, and he posted some Tweets that made headlines.
His biggest misstep, however, came during the summer when he departed early from a quarterback camp for high school players run by the Manning family in Louisiana. Manziel said it was a mutual decision after he overslept and missed meetings and activities.
Dat Nguyen, an All-America linebacker at Texas A&M in the 1990s and former assistant coach for the Aggies, lamented Manziel's mistakes, but noted what he's done for the program.
"I'm a little bit disappointed with what's going on down there," Nguyen said recently. "Going into the season I thought this would be the year for A&M to win a national championship and this has been a distraction. He made a bad decision and he's just got to move on ... but overall the guy has put A&M back on the map."
Former Texas A&M coach R.C. Slocum, who is now a special adviser to the school's president, has watched Manziel's career with great interest and is looking forward to seeing how he'll follow up his incredible first season.
"This young man has been in a position that no one has ever been in," Slocum said before the suspension was announced. "He's been a freshman and a 20-year-old winner of the Heisman Trophy, and he's done some great things with that and he's had a few things I'm sure he'd like to have a do-over with. And if I were advising him, I might have said, 'That's probably not in your best interests to do that or say that or be there,' but in terms of the upcoming season, I'm as anxious as anybody to see what happens and see what the results are."
Manziel was the main attraction at SEC Media Days, where he was peppered with questions but answered with the same cool and calm he often shows in the face of a pass rush.
"I don't feel like I've done anything that's catastrophic," Manziel said at the time. "Of course, I've made my mistakes. It's time to grow up."
The day before the Aggies reported for preseason practice, ESPN reported Manziel signed thousands of autographs for brokers in Texas, Florida and Connecticut, and cited unidentified sources who said Manziel was paid thousands for dollars for the signatures.
Manziel has been off-limits to the media since news broke of the NCAA investigation, but has been practicing with the Aggies.
Associated Press writer George Henry in Atlanta contributed to this report.
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