For Kansas City this season, Collins was 0-3 with a 4.15 ERA in 18 games.
Collins went on the disabled list on April 7 with a left flexor strain and returned from an injury rehab assignment with Omaha on May 5.
On June 26, Collins was optioned to Omaha and was with the Storm Chasers through the rest of their Triple-A championship season, getting the save in their title game victory over Pawtucket on Tuesday.
"He'll just mix in with the guys that are down there," manager Ned Yost said. "He'll fit in with everybody else down there."
Collins had a back injury that kept him from being brought back as an early September callup.
"He was healed by then, but he was still a little rusty so we wanted him to get some more innings under his belt and he was throwing the ball really well," Yost said.
Collins was an integral part of the bullpen for three years, 2011-13, pitching in a total of 206 games with a 3.51 ERA.
Collins was used in Friday night's 10-1 loss to the Tigers, working a perfect ninth inning.
"It's getting close to the end of the season and they're in a playoff push, and I just want to, hopefully, make my mark and give myself a chance to extend the season with them," Collins said.
Dick Kaegel is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.