The Chicago White Sox right-hander will be coming off the disabled list Tuesday night as he tries to get his tumultuous 2012 back on track at Fenway Park against a Red Sox lineup that will likely be lacking David Ortiz.
Humber (3-4, 6.01 ERA) threw the 21st perfect game in major league history April 21 at Seattle - San Francisco's Matt Cain has since thrown the 22nd - but the rest of his season has been far more forgettable. He went 2-4 with a 7.47 ERA in 10 starts following his gem, then landed on the DL with an elbow flexor strain.
He hasn't pitched in the majors in a month, but he's feeling better after allowing one run and two hits while walking none in six innings in the last of his three minor league rehab starts Thursday for Double-A Birmingham.
"I feel like my arm is responding well to what we've been doing," Humber told the Barons' official website. "I feel like I'm in good shape."
Humber's dismal stretch began April 26, when he allowed a career-high nine runs in five innings of a 10-3 home loss to the Red Sox.
"I got a lot of pitches up over the plate," he said that night. "To a team like that, they make you pay for it."
Left-handed hitters are batting .282 with a .500 slugging percentage against Humber this year. The top four hitters in Boston's lineup Monday - Jacoby Ellsbury, Carl Crawford, Ortiz and Adrian Gonzalez - are all lefties.
Ortiz, though, is likely out Tuesday after injuring his right Achilles on Gonzalez's three-run homer in the eighth inning of Boston's 5-1 series-opening win. The designated hitter leads the team in most offensive categories.
"He's a little upset and a little sore, but it doesn't look he pulled anything or tore anything," manager Bobby Valentine said. "It's probably going to be some days, though."
Switch-hitting catcher Jarrod Saltalamacchia went deep twice off Humber in April and Kevin Youkilis hit a grand slam for Boston.
Youkilis was traded to the White Sox (49-40) on June 24, and Monday's series opener was his first game at Fenway as a visitor. He got a standing ovation prior to his first at-bat and went 3 for 4 with a pair of doubles.
"It was a great ovation. It was just a cool thing from the fans," Youkilis said. "I can't thank them enough for all the support they've given me."
Boston still snapped a seven-game home skid to Chicago thanks to Gonzalez's tiebreaking homer. It was just the seventh of the season for the first baseman, who is batting .405 in his last 18 contests but struggling to hit for power.
The Red Sox (46-44) are hoping he and Jon Lester can make major improvements in the second half. When asked if the team can contend without better performances from Lester and Josh Beckett, Valentine said "no."
Lester (5-6, 4.49) has gotten an extended break since losing to the New York Yankees on July 8.
"I've got to keep grinding and working. I can't give up," Lester said. "I just have to go and relax and not think about my first half."
The left-hander is 2-4 with a 5.80 ERA in 10 starts at Fenway, but his only scoreless outing of the year came against the White Sox. He pitched seven innings in a 1-0 win April 28.