He's in New York now, and looking to prove himself again - on a Jets team that's young, hungry and highly proficient in trash talking on the practice field.
''Every single day, it's awesome,'' the wide receiver said after practice Wednesday. ''I mean, it's so competitive, and it's tough to create that in the offseason.''
Social media certainly makes it easier these days, as Marshall and cornerback Antonio Cromartie took to Twitter and Instagram to challenge each other in practice last week. For the record, Marshall started it, saying he was going to make it a long day for Cromartie and Darrelle Revis.
Well, not so much.
''I don't think he's getting the best of any of us right now,'' Cromartie said with a big smile. ''It's all fun and games.''
Except, of course, when Marshall drops a few passes here and there, causing teammates such as defensive tackle Sheldon Richardson to crow a little more.
''I dropped the ball yesterday and killed our offense and I've just been stinkin' it up in our competitive periods,'' Marshall said. ''And you've got young baby boy Richardson talking trash to me, talking about I get paid too much. ... When you look at the great teams, it's not really about execution on the field. I mean, it is about that, but it's about the chemistry off the field, too. Things that we're starting to do as an offense and what those guys are already doing as a defense, it's great. It's awesome.''
Marshall was acquired in a trade from the Bears in March after a season filled with losses, injuries and locker room issues. Chicago sent him to New York along with a seventh-round draft pick for a fifth-rounder - a low-risk, high-reward gamble in the Jets' minds.
He caught 61 passes for 721 yards - his first season under 1,000 since his rookie year in 2006 - and still had eight TDs despite finishing the season on injured reserve with broken ribs. The 6-foot-4 Marshall gives the Jets a big-time red-zone threat, a player who made a reputation of fighting for every catch and thriving in key moments in games.
''That's just my nature, I'm always trying to prove something,'' Marshall said. ''It doesn't matter if I'm playing pingpong or I'm in the fourth quarter with 10 seconds to go and we need a score, I'm always competitive and very passionate about whatever I'm doing.''
At 31, Marshall acknowledges that he has matured as a man after dealing with some legal incidents early in his career. He has been very open about having been diagnosed with borderline personality disorder a few years ago, and has been active in spreading mental health awareness.
The last several practices - particularly going up against Cromartie and Revis - have also proven to himself that he's physically healthy again.
''I really feel like I'm better now than I've ever been,'' he said. ''I feel great. Now, I'm starting to see the game differently, being older and having a lot of experience. Having all of that working for me and going up against those guys every single day, I'm excited about doing my job this year.''
Coach Todd Bowles has helped with that, installing competition periods in practices, in which it's offense vs. defense - and the loser, in some cases, has had to run gassers at the end of the session.
''It feels like it's a game, almost,'' Marshall said.
The Jets will head into training camp in July with Geno Smith as the projected starting quarterback. While many fans and media view that as a weak spot on a team that went 4-12 last season, Marshall likes what he has seen so far from the third-year signal caller.
''I was just blown away by his maturity and how much he knows,'' Marshall said. ''This kid is really smart, and the sky's the limit for him. He has everything around him that he needs, coaches and players, and all we have to do is do our jobs and let him work.''
Marshall isn't into making bold predictions for himself, knowing 1,500 yards receiving is a lofty if not unrealistic goal these days. He has made millions in the NFL and set his family up for life after football. Marshall also is capable of traveling anywhere he wants these days.
Except, perhaps, the playoffs. That's a place he has never been, the player with the most receptions in NFL history without a postseason appearance.
''Well, I didn't need a fresh start, but it's another opportunity to chase a dream,'' Marshall said, ''and that's to win.''
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