Jones then came up to hit for Gaby Sanchez and delivered a single to left-center, scoring both runners.
After Travis Snider singled, Michael McKenry sealed the victory with a three-run homer deep into the left field bleachers, assuring a victory in the rubber match of a three-game series.
Jeff Karstens (4-2) logged the win with five solid innings, yielding one run on three hits while walking one and striking out four for the Bucs, who won for the sixth time in eight games.
Chicago's Travis Wood (4-7) was saddled with the loss despite allowing just two runs on three hits over five innings. The left-hander walked three.
Wellington Castillo and Starlin Castro homered for the Cubs.
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