ST. LOUIS -- Cole Hamels will make his first start for the Cubs on Wednesday, while Tyler Chatwood heads to the bullpen to try to get back on track.
Hamels, acquired from the Rangers on Friday, is expected to join his new team on Saturday night. He will face the Pirates in the second game of a two-game series at PNC Park.
Cubs manager Joe Maddon and president of baseball operations Theo Epstein met with Chatwood after Friday's game. The Cubs opted to go with a five-man rotation rather than use six starters with the addition of Hamels, and Chatwood was the odd man out.
"I'm not going to lie, I've been grinding all year, and it hasn't been fun grinding that hard," Chatwood said. "Luckily, we've been winning games I've started, and that eases it a little. I'm excited to get back to what I know I can be."
The Cubs are 11-8 when Chatwood starts, and they have won his past five outings. But the high number of walks (85 across 94 innings) are a surprise, not only to the team, but also to him.

"I think there's some stuff I need to work out, so this will give me the opportunity to do that," Chatwood said. "Hopefully, whenever I start feeling good again, I can get back into the rotation."
The Cubs' decision was between Chatwood and Mike Montgomery, who has been starting in place of the injured Yu Darvish. They'll have to make another decision when Darvish is ready.
Chatwood, who signed a three-year deal with the Cubs in the offseason, is the focus for now.
"This guy works very hard. He cares about as much as you can care," Maddon said. "He's got a great arm. To this point, it just hasn't worked. We just have to get him out there and have him work with [pitching coach Jim Hickey] and [bullpen coach Lester Strode] and all the guys and get him back out there. I know it sounds illogical that he probably needs more work than less to work it through. You never know. Different mindset coming out of the bullpen, see if it just resets somehow for him. I'm really eager to see it."
It's been difficult, Chatwood said.
"It's hard to overhaul your mechanics, especially when you've done it [for so long] -- I think this is my eighth season in the big leagues," Chatwood said. "It's hard to do that in the middle of the year and try to get big league hitters out, especially when you're on a first-place team. I think I need to go back to what got me here and what I signed here for and go back to being myself. I think [this] will give me that opportunity to do that."

When the Cubs acquired Hamels, Chatwood didn't think about his role possibly changing.
"I know I'm not pitching to what I know I can," Chatwood said. "This gives me the opportunity to help us in a way and hopefully get back to what I can do and get back in the rotation."
Hamels last pitched on Monday for the Rangers. The Cubs are hopeful that Hamels can improve outside of Arlington's Globe Life Park, where he recorded a 6.41 ERA and gave up 16 home runs. Hamels owns a 1.22 ERA in five career starts at PNC Park, holding Pirates hitters to a .171 batting average in those contests.
Around the horn
• Shortstop Addison Russell was not in the starting lineup for a second straight game to give him time to heal from minor aches and pains, Maddon said.
"He's just been banged up a little bit," Maddon said. "He's fine. We both agreed maybe giving him two days right now will help."
Russell is expected to start on Sunday night.
• Alec Mills retired the six batters he faced in relief on Friday in his first callup to the Cubs, but he was optioned on Saturday to Triple-A Iowa. Cory Mazzoni was recalled from the Minor League team to give Chicago a fresh arm. He tossed a scoreless inning, striking out two, in the Cubs' 6-2 loss to the Cardinals.