Mahtook finished the night 3-for-5 with a double, two runs and four RBIs.
It was his first career multi-homer game and he has hit four home runs in his last six games.
In 127 games with the Bulls this season, Mahtook is hitting .294/.366/.467 with 12 home runs and 18 stolen bases.
The beneficiary of Mahtook's big game was left-hander Mike Montgomery, the Rays' No. 17 prospect. He struck out four batters and held the Tides to three runs on five hits and two walks in five innings. With the victory, he improved to 10-5 with a 4.29 ERA in 25 starts this season.
Teddy Cahill is a reporter for MLB.com. Follow him on Twitter at @tedcahill. This story was not subject to the approval of Major League Baseball or its clubs.