Whenever Red Sox pitchers have success against the New York Yankees' offense, they always make a point of stressing how difficult it is to achieve that success.

The mindset applies more to "mediocre" lines than it does those rare gems. There's something to be said for grinding one's way through innings and through starts against such a dangerous lineup, especially when that lineup is in its own park.

Such was the case Tuesday night for Jon Lester, who laid it all on the line in six admirable innings of a 6-4 win over the Yankees.

Lester was not at his best, particularly during a 33-pitch first inning in which he hit two batters and walked another. But he kept the damage to a minimum and never lost an early lead. On a hot night in Yankee Stadium against a first-place team that had won 13 of its last 18 games and entered the day leading the league in scoring, that's all you can ask for.

"This is really the best I've felt in a while as far as mechanics and throwing downhill," Lester said. "If you look at the hits I think two were really squared up. I'll take that against this lineup any day."

With the workmanlike performance, Lester can claim success against the Yankees on a historic level. He is now 8-1 lifetime vs. New York, 6-1 in The Bronx (both stadiums) and is the first Red Sox pitcher to win five straight starts against the Yankees since Reggie Cleveland, who did it in the mid-70s.

Having five straight wins against the Washington Nationals is noteworthy. Doing so on this stage takes it to another level, even if there are nights like Tuesday when things weren't quite the stuff of legend.

Staked to a 3-0 lead before he threw a pitch, Lester walked the second man he faced before hitting the third. It was a cutter that got in on Mark Teixeira and sent the Yankees slugger crumbling to the ground. He had to be removed from the game, but that didn't eliminate Lester's woes, which seemed to just be an extension of a five-start stretch in which his ERA was 6.52.

He gave up an RBI single to Robinson Cano with two outs, and then hit Russell Martin with a pitch — the seventh hit bastman in a span of six starts for Lester, who now leads the majors in that category.

New York had at least one runner on in all but one inning vs. Lester, but did not get any closer than the final margin. That was a testament to the lefty's ability to do enough against a team that rarely allows for it.

"They worked him hard," manager Terry Francona said. "He had to pitch out of the stretch pretty much the whole game. But he limited the damage real well. They had chances almost every inning to do something and he really kept it together."

Lester, who had two extra days of rest prior to this start, was asked what had led to his career record against the Yankees. "Luck," he said, ever hesitant to give himself any credit.

Seeing how hard he had to work Tuesday, his teammates know it's much more than that.