Ichiro Suzuki went 4-for-5 and stole a major league career-high four bases but his exploits proved futile as the Seattle Mariners lost 9-7 to the Boston Red Sox on Tuesday.

Despite Ichiro singling in the first, third, sixth and ninth innings, it was a Boston eight-run fourth off starter Joel Pineiro that was ultimately too costly for the Mariners' 18-hit attack.

Ichiro, who had a four-hit game for the second time this season, extended his hitting streak to 12 games to see his average improve six points to .327, but he scored just once and drove in no runs.

"Because of my speed, it is hard to steal unless my opponent gives me the chance to do so. If they give me the slightest chance, I will steal as much as I can," said Ichiro.

Manny Ramirez and David Ortiz hit consecutive homers to key Boston's eight-run fourth inning.

With the victory, the Red Sox remained seven games behind the New York Yankees.