The New England Patriots swapped out more than 2,500 Aaron Hernandez jerseys for free in Foxboro this weekend ... but TMZ has learned Tom Brady was NOT the most requested replacement. In fact, you'll never guess who was #1.

A rep for the Pats tells us ... the team happily shelled out roughly $250,000 to make sure any fan who had a Hernandez jersey could get a free replacement featuring a Pats player who's not currently facing murder charges.

We're told ... of the 2,500ish people who showed up to the stadium for the swap event, 30% of the fans were kids requesting new youth jerseys.

So, who was the most requested?? The honor goes to 5-time Pro Bowler VINCE WILFORK -- a 325-pound BEAST of a defensive tackle!!

Don't worry, Brady came in 2nd ... and we have a theory as to why -- everyone in Boston already has a Brady jersey.

FYI -- Tim Tebow wasn't in the top 5.