Jason Giambi belted his 12th-career grand slam as New York downed Toronto, 9-2, in the opener of a three-game set at Rogers Centre. Jorge Posada also homered for the streaking Yankees, who won their sixth straight and now lead the AL wild card race by four games over Detroit. The Tigers split a doubleheader with Texas on Tuesday. Johnny Damon finished 3-for-5 and drove in two runs for the Yankees, and Alex Rodriguez, who had homered in five straight games, finished 2-for-4 with a run scored. Phil Hughes (3-3) struggled early but settled down and pitched well to pick up the win. The young right-hander allowed just two runs -- one earned -- on three hits in six innings. Edwar Ramirez and Ross Ohlendorf, who was making his Yankees debut, finished things with three innings of scoreless relief. Russ Adams drove in a run for the Blue Jays, who lost their fourth straight game. Shaun Marcum (12-6) was touched for eight runs on eight hits in 4 1/3 innings en route to the loss. The Yankees jumped on top with a three-run second. New York quickly loaded the bases thanks to a Posada double, a Giambi walk and a Robinson Cano single. Marcum then uncorked a wild pitch, enabling Posada to cross the plate. After Melky Cabrera fanned, Damon slapped a two-run single up the middle. The Blue Jays bounced right back with two runs in home half. With runners at first and second and two down, Adams singled up the middle to drive in Gregg Zaun. Meanwhile, Cabreras throw to the infield got away, enabling John McDonald to cross the plate. Posada made it a 4-2 game in the third when he lined a two-out, solo homer, his 20th of the year, over the wall in right. New York then put things away in the fifth inning. The Yankees loaded the bases on a Bobby Abreu double, Rodriguezs infield single and a Posada walk before Giambi lifted his 13th homer of the year over the wall in left. The Yankees tacked on an insurance run in the eighth when Hideki Matsuis sacrifice fly to left chased Damon home. Game Notes Rodriguez has homered in five straight games five times in his brilliant 13- year career...New York now leads the season series 7-5...Ramirez struck out five in two innings of relief...The game was delayed for two minutes in the bottom of the eighth when Posada replaced his broken catchers mask...The Yankees remained five games behind Boston, who rallied to beat Tampa Bay, in the AL East.