Lester showed no ill effects from his injury last week and was splendid in a final tuneup for the playoffs, pitching into the seventh inning and leading the Red Sox to a 3-0 win over the Cleveland Indians on Thursday night.
"We were really happy," Boston manager Terry Francona said. "I don't think we thought it was an issue. We wouldn't have allowed him to pitch. It was really nice to see him pitch as well as he did for a lot of reasons."
Lester (15-8) gave up just two hits, walked one and struck out seven in 6 1/3 innings. He left after walking Jhonny Peralta with one out in the seventh.
The 25-year old left-hander was knocked out of last Friday night's loss to the New York Yankees by a liner off the bat of Melky Cabrera in the third-inning. He sustained a bruised quadriceps when the ball hit near his right knee.
Boston snapped its season-high six-game skid and handed the Indians their club record-tying 12th straight road loss.
Lester threw a side session Monday, which alleviated any of his fears.
"After my side day all the questions that were out there about my knee I didn't have anymore," Lester said. "I treated it as any other of my 31 other starts."
Jonathan Papelbon worked a perfect ninth for his 38th save.
Lester is in line to start Game 1 against the Los Angeles Angels next week, but the team hasn't made an announcement yet.
"I don't think it makes any sense to do it publicly until we get through guys' next starts," Francona said of his postseason rotation.
Lester, the club's best starter last postseason, relied mainly on his fastball in the first two innings, getting five flyouts and a pop out before mixing in other pitches more.
"It seemed like as the game went on he threw his cutter and his changeup more," Cleveland's Kelly Shoppach said. "But, I thought early -- maybe the first time through the order -- he wasn't as sharp. But as the game went on he got a feel for those other two pitches and kind of took off from there."
Cleveland starter Carlos Carrasco (0-4) left the game in the fourth after getting hit on the back of the leg by Jacoby Ellsbury's line drive. He was helped off the field after dropping to the ground behind the mound. The club said he has a bruised left quadriceps.
"He's OK -- missed his knee," Cleveland manager Eric Wedge said. "Obviously it caught a big part of his leg there, but he's going to be OK. He'll be sore for a while, but he'll be OK."
Red Sox catcher Victor Martinez, playing his first game against his former team since being dealt for right-hander Justin Masterson and two minor league pitchers on July 31, went 2 for 4 with a double and single.
Wedge, fired Wednesday but allowed to stay on through the remainder of the season, started his final series of a seven-year tenure with the club.
The Red Sox had most of their starting lineup back a day after resting all but two starters -- DH David Ortiz and shortstop Alex Gonzalez -- Wednesday. They clinched the wild card when the Texas Rangers lost to the Angels on Tuesday night.
Boston went ahead 1-0 when Ellsbury singled leading off the first, stole his major league-leading 68th base and advanced on Martinez's fielder's choice before scoring on Kevin Youkilis' sacrifice fly.
Ortiz and Jason Bay had RBI singles in the third.
Carrasco gave up three runs on nine hits in 3 1/3 innings.
Third baseman Mike Lowell fouled a ball hard off his left ankle in the second inning that had him writhing in pain behind the batter's circle.
After conferring with Francona, Lowell said he was alright to remain in the game. He had four at-bats before being lifted after seven innings. But the club's medical personnel were so concerned over the swelling in his ankle that they insisted he take some X-Rays. The X-Rays were negative and Lowell said he should be able to be the designated hitter on Friday night, though he will see how the ankle responds.
"It hit right above the shoe, where the mobility is,'' Lowell said. "I should be ready to go [Friday].''
Boston RF J.D. Drew was the only regular not in the lineup. Francona said before the game that his shoulder has been bothering him. ... It was Carrasco's fifth major league start. ... Indians SS Asdrubal Cabrera has been hampered by a left hamstring injury and did not play. ... Boston 3B Mike Lowell fouled a ball off his left foot in his first at-bat but stayed in the game. ... Lester finished with a 3.41 ERA.
ESPN.com's Pedro Gomez and The Associated Press contributed to this report.