Philadelphia tries to push its win streak to a season-high four games against a Cleveland Indians team trying to reignite its offense.
Hamels (1-5, 4.18 ERA) already has one fewer loss than all of last season, when he went 17-6. His strikeout-to-walk ratio - which has never been worse than 3.02 in a season - has dipped from 4.15 in 2012 to 1.95 in 2013.
The left-hander's control issues followed him into his last start, a 2-1 defeat to Arizona on Thursday in which he walked five and gave up six hits in six innings. Hamels took the loss as the Phillies (19-21) dropped to 1-7 when he takes the mound.
"I'm just not executing when I need to,'' said Hamels, who has issued 22 walks in 51 2-3 innings. ''That's my biggest issue so far, the walks. For me it's just to be able to go out, execute pitches and stop the walks. I have to correct what I can correct and that's what's going to make me a better player.''
Hamels also has had some tough luck of late. He has given up two or fewer runs in each of his last four starts and surrendered just 11 in his last six outings after giving up 13 in his first two.
The Phillies have scored just 16 runs for him in his eight starts, but showed potential to provide more after Tuesday night's 6-2 win to open this two-game set. John Mayberry went 3 for 4 with three RBIs for his first multihit game since April 19, raising his average 24 points to .242.
The Phillies have tallied 10 or more hits in four of their last eight games and are 12-4 when reaching double figures.
"I think it's a matter of time and we can end up having a good offense,'' Philadelphia manager Charlie Manuel said.
Cleveland (21-17) has endured a bit of an offensive slump on its end. During a six-game win streak from April 28-May 4, the Indians hit .357 with 14 homers and scored 53 runs, and still have won seven of their last 11 despite batting .231 with 11 home runs.
''I don't know if I'd call it a valley,'' manager Terry Francona said. ''We played a lot of baseball in a short amount of time. We were pretty hot. You can erupt any night or you can't score. I don't see it as a trend either way.''
The one constant for the Indians has been Michael Brantley, who accounted for Cleveland's offense Tuesday with a two-run single and has hit safely in five straight games. Brantley is hitting .361 over his last 10 games.
Corey Kluber (2-2, 5.64) could use more support like Brantley's. He was tagged for eight runs and 11 hits in 4 2-3 innings of Cleveland's 10-4 loss at Detroit on Friday. After a strong debut, the right-hander has a 9.58 ERA in his last two starts, surrendering 16 hits and six walks over 10 1-3 innings.
"I made too many mistakes with the cutter,'' Kluber said of his latest start. ''I left one over the plate to (Miguel) Cabrera, and they got a couple more hits off that exact same pitch.''