Derek Holland, the Texas Rangers lefthanded pitcher who has been on the disabled list since mid-June, will start a rehab assignment with the Round Rock Express on Friday, throwing 2 innings or 30 pitches.
Given that Holland is on the disabled list, my guess is that he will likely stay out on the rehab assignment until rosters expand on September 1, as he works on getting back up to speed after dealing with a shoulder problem that has sidelined him the past six weeks or so. Holland's stuff has deteriorated since missing the bulk of last season with shoulder issues, and it was indicated that the Rangers were going to work with Holland while he has been sidelined to adjust his mechanics to reduce the strain on his shoulder and hopefully improve his command.
The Rangers rotation right now consists of Cole Hamels, Yu Darvish, Martin Perez, A.J. Griffin and Lucas Harrell. Colby Lewis is also due back off the disabled list in late August, so its not quite clear whether Holland would re-join the rotation -- likely in place of whichever one of the Harrell/Griffin tandem Lewis doesn't replace -- or if he would be in the bullpen for the final month of the year.