Joe Saunders looked a little uncomfortable on the mound in the first inning, but that changed.
The Orioles' starting pitcher walked the first batter he faced, Elvis Andrus advanced Ian Kinsler to third, which then set up a Josh Hamilton RBI. The Orioles turned a double play on Hamilton's grounder and then got out of the inning on a long fly ball caught in center field by Adam Jones.
But, as the game progressed, so did Saunders' ability to work batters and get through innings.
The Baltimore Orioles took a 2-1 lead in the top of the sixth inning on an Adam Jones sacrifice fly. It was the pivotal moment in the game, as score was tied 1-1 until the top of the sixth.
Saunders went out of the game in the sixth with pats on the back from half the team before walking off the field. He finished the game with four strikeouts on a total of 77 pitches (46 strikes).
The Orioles brought in right-hander Darren O'Day to finish out the sixth.
The Orioles continued to make moves in the 7th inning and extended the score to 3-1 on a Nate McLouth RBI.
Brian Matusz replaced O'Day late in the eighth and ended the inning with a three-pitch strikeout of Josh Hamilton.
The Orioles extended their lead again, 4-1, in the top of the ninth on a Manny Machado line drive RBI single set up by a Robert Andino double that put a runner on third. Andino would later cross home to extend the lead to 5-1 after a McLouth sacrifice fly.
A last-ditch effort by the Rangers ended in the bottom of the ninth inning with the bases loaded after a David Murphy fly to left was caught by McLouth.
The Orioles will host the New York Yankees on Sunday for the first game of a best-of-five series.
Saunders, who was credited with the win, was also named the player of the game.