Peralta lifts Tigers over Red Sox, Rangers win to close in Fri Jun 21, 2013 2:35am EDT (Reuters) - Jhonny Peralta belted a two-run walk off homer in the bottom of the ninth to lift the Detroit Tigers to a 4-3 win over the Boston Red Sox in the battle of American League division leaders on Thursday. Peralta placed an Andrew Bailey slider over the left-field fence to move the Tigers (40-31) to their 40th win of the season while dropping the Red Sox to (44-31). Elsewhere Jordan Zimmermann notched up win number 10 and Ian Desmond homered for second straight game as Washington beat Colorado 5-1. Zimmermann (10-3) allowed just one unearned run on six hits with nine strikeouts as the Nationals improved to 36-36 while dropping the Rockies to 37-37. In Texas, the Rangers threw out Josh Donaldson trying to score from first base in the ninth to hold on to a 4-3 win over the Oakland Raiders. The result helped the Rangers (41-32) close within a game of their AL West leading rivals (43-32). Pittsburgh's Pedro Alvarez was responsible for all five of his side's runs as the Pirates took down division rival Cincinnati 5-3 and closed within half a game of the Reds. Alvarez clocked a two-run homer in the sixth after earlier driving in a run with a single in the third and then snapped a tie in the seventh with a three-run double. It pushed the Pirates to 43-30 but they remain in third in the NL Central behind the Reds (44-30) and St. Louis Cardinals (47-26). St. Louis were 6-1 winners over the Chicago Cubs (29-42) with Lance Lynn (10-1) also notching up win number 10 on the year. Evan Longoria hit two home runs to help Tampa Bay (38-35) to an 8-3 result over the New York Yankees (39-33). Newly acquired Pedro Ciriaco homered and drove in three runs to push the San Diego Padres (37-36) to a 6-3 win over the Los Angeles Dodgers (30-41). In a battle of struggling teams Carlos Pena hammered a three-run walk off homer in the 10th inning as the Houston Astros (28-46) beat the Milwaukee Brewers (29-42) 7-4. (Reporting by Ben Everill in Los Angeles.