The Angels had grabbed a 6-3 lead with three runs in the sixth but the Rangers responded quickly with three of their own in the next frame, ignited by Pierzynski's run-scoring single.
Then with two outs in the ninth, Pierzynski bashed a pitch from Ernesto Frieri (0-1) into the right field stands, putting the Rangers on top.
Joe Nathan came on to record his sixth save while Tanner Scheppers (2-0) got the decision with two innings of scoreless relief as Texas racked up a fourth straight triumph.
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