NEW YORK -- Too often is the word "potential" associated with Felix Doubront.

With a 5.67 ERA as of May 3, he had his start skipped, was thrown into the bullpen and asked to watch as 23-year-old prospect Allen Webster, who had one career start in the Majors until then, took his spot.

It was only temporary, the Red Sox said, but with Webster's pedigree and success in the Minors, whispers about a more permanent replacement could be heard even in the most crowded room.

Potential wasn't going to do much for Doubront then, on a first-place team in the ultra-competitive American League East, where the thought of one extra win could mean the difference between a do-or-die Wild Card game and the luxury of a five-game series come October.

Performance was needed, and suddenly, the Red Sox pulled their own version of now-you-see-me, now-you-don't. The old Doubront disappeared. A new one arrived. On Saturday night at Yankee Stadium, with the Yankees thinking of a series sweep on the heels of the healthy returns of Kevin Youkilis and Mark Teixeira, Doubront had far more than potential.

Posting his fourth consecutive impressive outing, Doubront silenced Yankee Stadium with six innings of one-run ball, striking out six as the Red Sox poured it on in an 11-1 win.

"He didn't make too many mistakes," said Yankees outfielder Vernon Wells, who entered the game with a .309 average against left-handers but went 0-for-4 against Doubront. "I was talking to Tex during the game and he was [saying] when [Doubront] made his pitches away, they were away. And when he wanted to come in, he was throwing the ball well in.

"He threw the ball pretty well."

Through the first two innings, Doubront was unsteady. Manager John Farrell was interviewed on the mid-game broadcast on FOX Sports and said Doubront was missing his spots and it was a good thing Mike Napoli had just hit a grand slam, because "we're going to need every run" tonight.

Turns out, they didn't need much.

"We've seen it a number of times before," Farrell said afterward. "Taking those first couple of innings to find his way and settle in, find a rhythm. As the night went on, his tempo, his pace picked up and there were a lot more quality strikes within the strike zone.

"He's making steady progress each time he walks to the mound. Tonight was another step."

Over his last four starts, Doubront has thrown 23 innings and allowed just 19 hits while lowering his ERA from 6.40 to 4.88. He's also struck out 24 batters.

While he's in his fourth season in the Majors, it's easy to forget Doubront is only 25 years old, and he just eclipsed the 250-inning mark for his career on Saturday.

Time is required to learn, develop confidence and transfer that to success on the mound.

So Doubront stopped looking at his numbers. He doesn't care. Not yet.

"I don't worry too much about that," he said. "I just go up there and when you see the results, the numbers are going to be better. That's what I've been working on. Forget about the numbers. Every successful outing that I have the numbers are going to get better."

Some of those numbers are already impressive, particularly his strikeouts, which only enhance the Red Sox's belief that Doubront may be the most talented pitcher on the staff.

With 59 strikeouts in 55 1/3 innings, Doubront is averaging 9.6 per nine innings, the highest rate among all Major League left-handers with at least 40 innings. Over parts of his four-year career, he's already posted the fourth-highest strikeout rate all-time among Red Sox pitchers with at least 200 career innings.

"Now that I have everything together, I feel [more confidence]," Doubront said. "The moment I see swinging and missing because I throw a good pitch, I want to go up there and challenge the hitter."

"He's got great stuff," said catcher Jarrod Saltalamacchia. "He's definitely not a No. 4 or 5 starter. Him being young and still learning who he is and how he pitches, that's where he's at right now, but I definitely see him at the top of our rotation for a long time."

There's been at least one expectation for Doubront thus far: He dominates the Yankees.

In nine career games against the Bronx Bombers, a span of 35 2/3 innings, Doubront has posted a 2.52 ERA. He's allowed just 25 hits and struck out 38.

Why is he so good against the Yankees?

"The adrenaline, facing those guys, my respect for those guys," he said.

And experience. More learning, he said. He has a better understanding for each hitter he faces.

Potential indicates that Doubront could be a future All-Star.

"I hope so," he said.

Talk potential later. For now, Doubront is performing.