The Buccaneers took their first lead of the game after Lavonte David returned an interception for a touchdown with 4:25 left in the third quarter.
The Chargers came right back, with Philip Rivers throwing a 40-yard pass to Tyrell Williams to put the Chargers back in the lead, 21-17.
That drive covered 75 yards in five plays in under three minutes. So, the stage is set for a wild finish.
Both teams need the game badly. The Chargers are 5-6. The Bucs are 6-5 and can catch the Falcons in the NFC South standings with a win.
In the first half Chargers running back Melvin Gordon scored his 10th rushing touchdown of the season. Gordon is over 100 total yards for the game.