Astros starter Dallas Keuchel had a brief run of perfection Saturday night, but a decidedly imperfect first inning boosted the Mariners to a 3-1 win before 21,085. Keuchel (5-8) retired 11 batters in a row at one point and allowed one hit from the second through the seventh innings after Seattle used three hits, two walks and a groundout dribbler to score three times in the first. He settled in after the rough start, allowing four hits with eight strikeouts through seven innings, with help from catcher Cody Clark, who threw out two baserunners attempting to steal second, and left fielder Robbie Grossman’s catch of Nick Franklin’s sinking liner in [...]