Blanks, who was called up last week from Triple-A Portland, had the first RBI of his career with a double in the second. The 6-6, 285-pound left fielder added a two-run double in the fifth that gave San Diego a 6-1 advantage.
The Rangers dropped out of first place for the first time since May 5. They are a half-game behind the Los Angeles Angels in the American League West.
Kevin Correia (5-5) struck out a career-high nine in seven innings, his fifth straight start pitching at least six innings. The right-hander’s previous high strikeout game was eight against Atlanta on August 10, 2005.
Rookie Derek Holland (1-5) allowed 13 hits and seven runs in 5 2/3 innings as Texas had its three-game winning streak snapped.
Chris Davis homered in the second, and Michael Young and Andruw Jones each had RBI doubles for the Rangers.
