As far as Red Sox pitchers -- past and present -- Lester's name and statistics can be mentioned in the same breath as modern-day aces Pedro Martinez and Roger Clemens. The term "ace" is one that's tossed around too often in this game but rarely defines exactly the type of success a pitcher needs to be classified as such.
"To me, it's a guy who you're extremely confident you're going to get a win out of every time he goes to the mound," said Red Sox reliever Daniel Bard. "Not only that, [when the bullpen staff] sees Jon cruising like that, sometimes we think we're going to take a back seat because he might go all the way here. That's a feeling you only get with a few guys. That defines an ace from my perspective."
Lester is the model ace.
He proved it again Saturday when he led the Red Sox to a 7-3 victory over the New York Yankees. Lester worked seven scoreless innings and allowed only two hits (both came in the sixth inning) with three walks and eight strikeouts. He's 19-8 this season with one start remaining before the end of the regular season.
"He was pretty good. He was great," said Red Sox catcher Victor Martinez. "He kept the hitters off balance and did a great job tonight."
Lester has won six straight and became the first Red Sox left-hander since Bob Ojeda (1983) to accomplish the feat. It also marks the most wins in a season by a Sox southpaw since Mel Parnell's 21 wins in 1953.
Lester tossed his eighth scoreless start of the season Saturday and is tied for the fifth-most in that category by a Red Sox pitcher since 1920. Pedro Martinez recorded 10 scoreless starts in a season twice, in 2000 and 2002; he won the Cy Young in 2000. Derek Lowe (2002) and Clemens (1988) each posted nine scoreless starts. Daisuke Matsuzaka recorded eight in 2008.
Along with fellow Red Sox starter Clay Buchholz (16-7, 2.39 ERA), Lester should be considered for the Cy Young Award. After all, the left-hander has 204 innings pitched, 220 strikeouts and a 2.96 ERA.
"It amazes me he's not in the Cy Young talk," Bard said. "He might be by the end of the year. To me, the two things you can control as a pitcher are innings -- going deep into games -- and striking guys out. The wins and ERA are byproducts of that, so those can be skewed either way, too, with a lot of luck. But the things you can control are going deep into games and striking guys out. That's dominance right there. He does both of those things pretty well."
The southpaw also improved to 3-0 with a 2.13 ERA in four starts against the Yankees this season, and he has not allowed a run in two starts at Yankee Stadium. Safe to say he gets fired up when he faces the Bronx Bombers.
"It's fun. It's Yankee Stadium," Lester said. "You're pitching against, if not the best, one of the best teams in the league. It's a tough lineup to navigate through and it's kind of fun going out there pitching against them and seeing what you can do. It's kind of a cool deal to do."
When Lester was developing and honing his skills in the minors, the Red Sox had a strict pitch count and a limit to the innings Lester could pitch in a season. That would frustrate him.
"It's nice not to worry about that anymore," he said. "Here's the ball and see what happens. It's nice to take some pressure off of me, to go out and pitch and not worry about [pitch counts]. It's nice the reins are no longer there and I don't have to worry about it."
All that earlier frustration has paid dividends the past three seasons, and Lester has reached the 200-inning plateau each year. He's has proved to be one of those pitchers who gets better the more he pitches. He said after Saturday's win that he still feels strong, but his body also knows it's September.
It's become evident he prides himself on reaching that mark each season.
"Absolutely," he said. "Getting up to the big leagues, that's the number you're trying to get to. You're trying to make all your starts and throw 200 innings, and now that I've done it for a couple of years, I expect it of myself. That number is more important to me than any other stat that's out there."
There's one more number he would like to reach, but he's being humble about the next possible milestone -- reaching 20 victories. He'll say he would rather make the postseason than win 20, and even though he's genuine when he makes that statement, accomplishing that next goal would be special.
"It would be nice, but we're trying to make a little bit of a run here and make the playoffs," he said. "That would mean more than 20 wins, especially with how our season has gone. Getting into the playoffs would be a little more rewarding than 20 wins."
Joe McDonald covers the Red Sox and the Bruins for ESPNBoston.com.