Uggla's double put Florida in front 4-1 with two outs in the top of the eighth.
Chris Coghlan led Florida with two hits and one RBI.
Jorge Cantu added a hit and a sacrifice fly for the Marlins, who have won the first two contests in the regular season-ending three-game series.
Winner Anibal Sanchez (4-8) yielded a run and five hits in seven innings.
Closer Leo Nunez earned his 26th save with a scoreless ninth.
Jayson Werth led Philadelphia with two hits -- one an eighth-inning two-run homer.
Ryan Howard hit a solo shot and scored twice for the Phillies, who have lost three in a row.
The losing pitcher was starter Cole Hamels (10-11).
Despite its loss, Philadelphia clinched home field advantage in the NL playoffs.
Aaron Carter is still in love with Hilary Duff
Ray Liotta sues skin care company over use of likeness