After loading the bases in the bottom of the first inning and failing to score, the Pirates failed to threaten to score the rest of the game, as Mat Latos, J.J. Hoover, Aroldis Chapman and Alfredo Simon combined for the shutout.
The Reds scored all five runs in the first half of the ball game, highlighted by a Todd Frazier home run in the second and a Drew Stubbs two-run home run in the third.
Latos pitched six innings, striking out a career-high 11 batters and allowing just two hits.
His mound opponent, Charlie Morton, struggled to find a rhythm as he allowed five runs (four earned) in six innings on seven hits, including the two homers.
The Pirates return to action at home on Tuesday, as they begin a series with the NL East-leading Washington Nationals.
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