The teams combined for six home runs -- three for each club -- but it was the base hit by Betemit that gave the Orioles the lead for good.
Baltimore trailed 5-4 heading into the eighth, but Nolan Reimold singled to open the inning. Reimold stole second, went to third on an infield single by Nick Markakis and Matt Weiters walked to load the bases.
Betemit then came through with a two-out single to center that gave Baltimore a 6-5 lead. The go-ahead run was charged to Darren Oliver (0-1).
Darren O'Day (1-0) threw a scoreless inning of relief to get the win.
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