Alburquerque signed a Minor League deal with the Royals in January and is 2-1 with a 2.63 ERA and two saves for Omaha this season. His last full season in the Majors was in 2015, when he went 4-1 with a 4.21 ERA in 67 appearances for the Tigers. The 30-year-old pitched in two games for the Angels last year, allowing three runs (one earned) in two innings.
• Junis optioned to Omaha after first MLB win
Maness, who is only nine months removed from primary repair surgery on his ulnar collateral ligament, also signed with Kansas City as a Minor League free agent before the 2017 season. He pitched in three games for the Storm Chasers while recording a 1.50 ERA. The 28-year-old sustained the elbow injury with the Cardinals in 2016 that caused him to miss the final six weeks of the season. He went 2-2 with a 3.41 ERA in 29 games for St. Louis last year.
The pitchers, who will be making their first tour with the big league team this season, were expected to arrive in time for Wednesday night's game.
Colon, a former first-round pick in the 2010 Draft, is hitting .176 with a walk and a run scored in seven games with the Royals this season.
"This was a decision that could have, quite frankly, been made out of Spring Training," Yost said. "We wanted to hold on as long as we could to see if we could get it to work. We just feel like we had other options."
Yost said there was still a possibility that Colon, who scored the winning run in the 2014 American League Wild Card Game, could remain with the club if it is unable to work out a trade. If the middle infielder clears waivers and does not request his release, he can accept an assignment to Omaha after seven days.
O'Brien, 26, batted .141 with five home runs and nine RBIs for the D-backs in 2016, but he did not appear in a game for the Royals this season. He was hitting .162 with three home runs and six RBIs for Omaha.
Junis, who is ranked as the club's No. 5 prospect by MLBPipeline.com, threw two scoreless innings for the Royals while walking four and giving up one hit. He is 1-2 with a 3.52 ERA in four starts for the Storm Chasers in 2017.
J. Scott Butherus is a contributor to MLB.com based in St. Petersburg. This story was not subject to the approval of Major League Baseball or its clubs.