Park staff in Tampa, Florida, were patrolling closed parks when they noticed someone working out in a park downtown.
It was NFL star Tom Brady, said Tampa Mayor Jane Castor in a briefing on Monday.
"Now, I always tell people, I’m not one to gossip so you didn’t hear this from me," she said.
"But you know our parks are closed down and so a lot of our parks staff, they patrol around just to make sure that people aren’t doing contact sports and things like that, and saw an individual working out in one of our downtown parks. And she went over to tell him that it was closed, and it was Tom Brady."
Brady was given a citation for being in the park, she added.
The 42-year-old is widely considered the greatest quarterback of all time, spending almost his entire NFL career -- 20 seasons -- with the New England Patriots, winning six of the nine Super Bowls he reached.
He is now the quarterback for the Tampa Bay Buccaneers, after signing a multi-year contract with the NFL team in March.