To make room on the active roster for Atchison, the Mets will option Jordany Valdespin to Triple-A Las Vegas.
Atchison has not pitched since May 13 when he was diagnosed with bone spurs and loose bodies in his right elbow.
He was activated from the disabled list on June 18, but suffered a strained groin while warming up to pitch during that game.
Atchison has made 19 appearances in 35 games and pitched to a 4.50 ERA this season.
Valdespin has hit just .189 with four home runs and 16 RBI in 143 plate appearances this season. He went 0-for-1 on Saturday and has one hit since June 16.
The Mets will be playing with a short bench tomorrow, but considering they're going into an extended break, LaTroy Hawkins is unavailable, and the bullpen has been overtaxed over the last two nights, I have no problem with adding the extra arm for tomorrow's game. They need a fresh reliever available tomorrow, and if Atchison is ready, this move works for me.
As for Valdespin, it was just a matter of time before he was getting sent out. As I said earlier, he is the last man on the roster and is not being utilized; at that point, he becomes dead weight and the Mets are effectively playing with a short roster on a daily basis. If the bullpen wasn't so overworked, it would have made sense to wait until Justin Turner was ready, but that would have just prolonged the inevitable.