The Texas Rangers have demoted Shawn Tolleson and named Sam Dyson closer, Jeff Banister announced.

Tolleson, who is tied with Ryan Madson and Steve Cishek for the American League lead with 11 saves, suffered his fourth blown save Tuesday night.

Dyson has saved two games in the Rangers' last three wins. He's tied for second in the AL with 10 saves.

"Shawn will still pitch, just in different situations," Banister said. "You look at his body of work and he's been efficient, effective and sits atop the AL in saves. This is a tough stretch for him."