One out later, Nava came up and belted a 1-1 pitch from Wei-Yin Chen (0-1) over Fenway Park's left-field "Green Monster" wall for a decisive, three-run shot that gave Boston the opener of a three-game series.
Clay Buchholz (2-0) worked around four walks and three hits en route to seven scoreless innings, picking up the victory. The right-hander struck out eight.
Chen finished with three runs allowed over 6 1/3 frames, surrendering five hits and a pair of walks while fanning three.
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