KANSAS CITY, Mo. -- The Royals got even more young and inexperienced in the bullpen Monday when they sent veteran left-handers Tim Collins and Francisley Bueno to the disabled list.
The Royals called up rookie left-hander Donnie Joseph and rookie right-hander Micheal Mariot from Triple-A Omaha to take their places.
Manager Ned Yost said before the game he wasn't going to take baby steps with either Joseph or Mariot. Joseph is now the only left-hander in the bullpen.
"We can't afford to go slow with them," Yost said. "We will need them."
Joseph, 26, pitched in six games for the Royals last season while Mariot, 25, is making his first trip to the big leagues.
"I've always liked Mariot," Yost said. "He had a good camp with us last year and a better camp this year. Good fastball and good slider.
Watch the Royals Live pregame and postgame shows before and after every Kansas City Royals game on FOX Sports Kansas City.
"Donnie, I've always liked him, too. He's good at situational matchups (versus lefties)."
Collins, Yost said, indicated after Sunday's loss that he was experiencing some tightness in his elbow. Collins gave up three more runs Sunday and now has a 36.00 ERA.
"I knew something had to be wrong because while he struggles with his fastball command a lot," Yost said, "he usually can get through it with commanding his secondary pitches. But he hasn't been able to do that."
Yost said Collins had an MRI today and the results were "clean."
"It's just some inflammation in there," Yost said. "We'll shut him down for four or five days and go from there."
Bueno suffered a sprain of his pinky finger on his throwing hand while trying to stop a ground ball in the ninth on Sunday. He will be shut down for only five or six days.
"But we can't afford to have someone down that long," Yost said. "We needed another body or two."
Meanwhile, right-hander Louis Coleman, on the disabled list because of a bruised finger, was back in the Kansas City area on Monday. He threw a simulated game on Saturday in Arizona and is expected to go on a rehab assignment with Omaha on Tuesday. He could rejoin the club this weekend.
Mariot, an eighth-round pick in 2010, was 4-5 with Omaha in 2013 with a 3.56 ERA. He saved 11 games.
Joseph nearly made the Royals out of spring training but, like Collins, struggles with his command.
"My goal is to do what I can to help this team win," Joseph said. "And that means I have to throw strikes."
You can follow Jeffrey Flanagan on Twitter at @jflanagankc or email jeffreyflanagan6@gmail.com.
