And it was his worst performance against them at home.
Lester (8-6) allowed four hits in eight innings in Boston's 1-0 victory Friday night. That wasn't as good as the no-hitter he threw against them on May 19, 2008 or the one hit he gave them in eight scoreless innings on July 18, 2006.
"Obviously, he was terrific," Red Sox manager Terry Francona said. "He had to be because their guy was so good."
Brian Bannister (6-7) limited Boston to one hit through seven innings before leaving a pitch too far over the plate that Dustin Pedroia was able to lift off the left-field wall for the tiebreaking double in the eighth.
"I lost the game because I gave up a hit to the reigning MVP of the league," Bannister said. "I'm extremely disappointed that I lost this game for our team, but it was as good a game as I've ever pitched in my life."
Lester is 3-1 against the Royals, losing only in Kansas City. In Boston, he's given them five hits and eight walks with 21 strikeouts in 25 innings.
"You still have to go out and execute pitches, regardless if you are facing a high school team, or you're facing the Yankees, or you're facing the Royals," he said. "It doesn't matter."
Mark Teahen had three of the four hits off Lester then popped up for the final out in the ninth against Jonathan Papelbon, who got his 23rd save in 25 opportunities. Teahen had the only hit in Lester's one-hit performance three years ago.
"I don't think [I'm] really solving him," Teahen said. "I was able to stay simple enough in my approach to barrel some balls. ... He was on his game tonight."
Lester walked two and had eight strikeouts. Bannister went 7 2/3 innings, giving up three hits and four walks while striking out seven.
Mark Kotsay, playing with a calf injury, led off the bottom of the eighth against Bannister with a clean single to center. Aaron Bates, called up to the majors for the first time on Monday, pinch ran and took second on Nick Green's sacrifice bunt.
Bannister threw a wild pitch in the dirt and Bates moved to third. Pedroia, coming off consecutive three-hit games, hit his first ball out of the infield on Friday for his double.
"I never squared up a ball [on his first three at-bats] and so my biggest thing was try and hit it on the barrel," Pedroia said. "That's the worst feeling as a pitcher to throw that good and not win. For their guy, he threw the ball great. And Lester was just a little bit better, I guess."
Both pitchers entered the game on a roll. Lester was 4-1 in his previous seven starts with a 1.74 ERA. Bannister had a 2.48 ERA in his last six starts but just a 2/3 record.
On Friday, he held the Red Sox hitless through four innings, allowing only walks to Youkilis in the first and J.D. Drew in the third.
With Green up, Kotsay took off for second and was caught in a rundown. Ellsbury raced home and appeared to slide in before catcher Miguel Olivo could tag him. After being called out Ellsbury bounced his helmet hard and was ejected by plate umpire Derryl Cousins.
But Rocco Baldelli, his replacement in center field came up with a big play in the seventh.
Jose Guillen led off and reached first on a throwing error by third baseman Youkilis then took second on Teahan's single, his sixth hit in eight at-bats in the series.
Olivo sent Baldelli to the warning track in straightaway center. Both runners tried to advance. Guillen made it to third, but Teahen was called out at second when he overslid the bag and was tagged by second baseman Pedroia.
The Royals obtained SS Yuniesky Betancourt and cash considerations from Seattle for RHP Danny Cortes and LHP Derrick Saito. ... Guillen has gone 13 games without an extra-base hit. ... Ortiz, who has 10 homers in his last 30 games, went 0 for 4 with three strikeouts. ... Kansas City hasn't had a day off in 18 days.