Tigers' Fister strikes out a record nine in a row Thu Sep 27, 2012 6:26pm EDT (Reuters) - Detroit pitcher Doug Fister set an American League record by striking out nine consecutive batters as the first-place Tigers beat the Kansas City Royals 5-4 on Thursday to boost their playoff hopes. The win temporarily moved Detroit 1-1/2 games ahead of the Chicago White Sox in the American League Central division. The White Sox play the Tampa Bay Rays later on Thursday. Fister's strikeout streak began with the Royals' final out of the fourth inning and ended with Salvador Perez's ground out to end the seventh. Four American League pitchers had struck out eight batters in a row. Hall of Famer Nolan Ryan accomplished it twice. Blake Stein, Roger Clemens and Ron Davis each did it once. New York Mets' Hall of Famer Tom Seaver holds the Major League record of 10, set in 1970. Fister, a tall right-hander with a 10-9 record, left the game after 7-2/3 innings with a 4-3 lead, but did not figure in the decision. Detroit won the game on Alex Avila's run-scoring groundout in the ninth. In the American League West, the Texas Rangers strengthened their division lead with a 9-7 victory over the Oakland Athletics. The win, highlighted by pitcher Matt Harrison 18th victory, gave the two-time AL champions a four-game lead over the Athletics with six games remaining in the regular season. Harrison (18-10) pitched six innings, giving up four runs and seven hits, in becoming the Rangers' first 18-game winner since Kenny Rogers in 2004. In the National League, the playoff-bound San Francisco Giants have decided not to use currently suspended slugger Melky Cabrera in the postseason. Cabrera, serving a 50-game ban for a positive test for testosterone, would become eligible to play if the Giants' postseason goes beyond five games. "It's a decision we had to make early because Melky would have to start rehabbing, and we have decided to develop our roster," Giants manager Bruce Bochy told reporters. Cabrera, the All-Star Game's most valuable player, was batting .346 with 11 home runs and 60 runs batted in when he was suspended on August 15. "Our guys have done a good job of stepping up when we needed them to," Bochy said. I think it's for the best of this club if you've looked at how they've played and all we've been through. These guys have really done a great job. The Giants, the 2010 World Series champions, clinched the National League West pennant last week. Reporting by Gene Cherry in Raleigh, North Carolina