ARLINGTON, TX - AUGUST 24: Darren O'Day #56 of the Texas Rangers pitches against the Boston Red Sox at Rangers Ballpark in Arlington on August 24, 2011 in Arlington, Texas. The Red Sox beat the Rangers 13-2. (Photo by Tom Pennington/Getty Images)
To make room on the 25 man roster, Darren O'Day is headed to the disabled list with shoulder inflammation, and Nelson Cruz is going to the disabled list because of his strained hamstring.
Both Martin and Hamburger will be making their major league debuts once they enter a game.
O'Day last appeared on August 24, and thus will be eligible to be activated on September 8.
There is still no official word yet on who will be removed from the 40 man roster to make room for Hamburger. Evan Grant suspects that either Ryan Tucker or Tim Wood will be put on waivers for the purpose of being outrighted to the minor leagues.
When we have news on the 40 man roster move, we will update.
UPDATE -- Ryan Tucker is being released to make room on the 40 man roster.