Bryce Miller stymied the host Houston Astros by logging seven scoreless innings on Monday as the Seattle Mariners gained ground in the American League playoff race with a 6-1 win. Jorge Polanco, Julio Rodriguez and Randy Arozarena each had an RBI double for Seattle (81-76), which closed within 1 1/2 games of the final AL wild-card spot. Cal Raleigh and Justin Turner also supplied RBIs. Miller (12-8) scattered two hits and two walks while striking out five, including consecutive punchouts with runners on second and third in the seventh to keep the Mariners ahead 2-0. Troy Taylor worked the eighth and Eduard Bazardo pitched the ninth as Seattle improved to 12-6 since Sept. 4. Hunter Brown (11-9) was just as stingy as Miller over his six innings for Houston (85-72), which would have clinched its fourth straight AL West title with a win on Monday. The right-hander limited the Mariners to one run on three hits and three walks while fanning eight. The Astros lead second-place Seattle in…..