Hamels has been with Texas since 2015.
Hamels has been in terrible form recently, allowing 25 earned runs in his last 22 innings pitched, raising his ERA to 4.72. The lefty said he wasn't sure yet when he would make his first start for Chicago. Hamels' velocity has bounced back after an alarming downturn early in the season, but he's still been plagued by home runs more so than at any point in his career; thus far, just over one out of five fly-balls allowed by Hamels has resulted in a long ball. Chatwood walked six batters in the Cubs' 7-6 walk-off win over Arizona on Thursday, giving him 85 walks in 94 innings. He's pitched some really big games against teams I've been involved with and has done really well.More news: Despite Helsinki criticism, Trump's job approval up a point from last month
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Hamels carried a 3.61 ERA at the end of June, before a rough July (1-3, 11.12 ERA) sent his ERA climbing and his price dropping.
"It's always that chase for that World Series, you start realize how hard it is to achieve", Hamels said.
Quintana was acquired in a costly trade with the crosstown White Sox last July that included touted prospects Eloy Jimenez and Dylan Cease.
Butler will join the Rangers' roster. Lacy, an 11th-round pick in last year's draft out of Creighton, was assigned to Class A Down East. Butler is 1-1 with a 4.08 ERA in eight appearances this year. He was sidelined for about three months with a groin injury before recently returning.