MINNEAPOLIS -- Rangers pitcher Yu Darvish, on the disabled list with discomfort in his right shoulder, threw 29 pitches in a bullpen session on Friday at Target Field, and the next step is a start in the Minor Leagues.
Darvish is scheduled to pitch three innings and 45 pitches for Double-A Frisco at Northwest Arkansas on Monday. It's expected to be the first of multiple starts on medical rehabilitation assignment as Darvish hasn't pitched since June 8 against the Astros.
That was the last of three starts made after a 14-month absence following Tommy John elbow reconstruction surgery.
"I think that's necessary to have multiple outings to build him up to the point where he is Major League ready," Rangers manager Jeff Banister said. "He has worked his tail off. He has been busting his tail to get to this point as he has since his surgery."
Reliever Keone Kela, who is on the disabled list recovering from elbow surgery, is also ready for a rehab assignment after throwing a 25-pitch simulated game at Triple-A Round Rock on Thursday.
Kela is expected to pitch one inning for Round Rock on Monday in New Orleans, and then have multiple outings later in the week for Frisco. He could be ready after the All-Star break when the second half resumes on July 15 against the Cubs in Chicago.
"There is not going to be any urgency with either one of them," Banister said. "I don't think we've indicated we would be urgent. We want both of them for the long haul. Setbacks do happen, but we don't want to create them."
Tolleson relates to Kershaw
Rangers reliever Shawn Tolleson and Dodgers pitcher Clayton Kershaw are close friends and former teammates. Now they have something else in common. Both have had trouble with the L5-S1 disk in their lower back.
Tolleson missed most of the 2013 season with a herniated disk that required surgery. Kershaw was placed on the disabled list with a herniated disk on Thursday, but Tolleson, after speaking with his friend, said his was more severe back in 2013.
"From my understanding, he's got a small herniation," Tolleson said. "It's the same disk I had an issue with, but it sounds like it's not too bad. He got a shot, hopefully that will calm it down and he won't have to go through the surgery.
"His pain is very localized to his back. I had some stinging sensations going down my leg. He hates being on the disabled list. I told him I was praying for him. Every case is different. I told him if he needed help with a good sleeping position or sitting on a plane, let me know. But it sounds like he's got guys who know what they are doing."
Tolleson's surgery was a boon to the Rangers. The Dodgers took him off the 40-man roster after the 2013 season and the Rangers claimed him off waivers.
• Rangers catcher Robinson Chirinos, who wasn't in the lineup on Friday, is 1-for-18 since sustaining a bruised right thumb against the Cardinals on June 19, and Banister said, "I know it's been sore. I've got to believe there is some effect. But I don't think he would use that as an excuse."
• Outfielder Ian Desmond was the Rangers' Player of the Month for June after hitting .358 with a .423 on-base percentage and a .596 slugging percentage. It's the second straight month he has won the award.
• Cole Hamels and Martin Perez were both 4-0 in June. It's the fifth time in club history the Rangers have had two pitchers go undefeated in a month with at least four wins. The others were Kevin Brown (4-0) and Nolan Ryan (4-0) in April 1990; Bobby Witt (5-0) and Ryan (4-0) in July 1990; Rick Helling (5-0) and Aaron Sele (5-0) in April 1998; and Matt Harrison (4-0) and Derek Holland (4-0) in September 2011.
T.R. Sullivan has covered the Rangers since 1989, and for MLB.com since 2006. Follow him on Twitter @Sullivan_Ranger and listen to his podcast. This story was not subject to the approval of Major League Baseball or its clubs.