It is official, he's going to start a game in Tuesday's doubleheader.
No word yet which game it will be, but apparently, he'll start one game, and Joaquin Benoit will start the other. He could go in game #1, and then immediately be sent down to make room for a reliever to be added to fortify the pen.
Also no word yet on who will be sent down to make room for Volquez, or whether he'll stay in the rotation, although the word seems to be that if he pitches well on Tuesday, he'll get more starts.