"To be able to not contribute at all on the field and just having to watch, it's not fun for any competitive person," Castro said. "To finally be back and to be able to help the team, that's what I'm most excited for."
Castro said he went through a series of blocking drills and progressions to ensure he was comfortable with reaction times behind the plate. He caught a bullpen seission from Scott Kazmir on Wednesday and reported no discomfort.
Prior to going on the DL, Castro had a four-game hitting streak and three straight games with a double.
"Getting Jason back in the lineup brings a lot of presence back behind the plate," said Astros manager A.J. Hinch. "How he handles the pitching staff, the catch-throw ability. He was swinging a good bat when he went down in Minnesota."
• Carlos Gomez reported no soreness after undergoing rotating exercises that simulated a swing on Thursday. He was able to throw, run and shag fly balls during batting practice but was unsure when he would be able to swing a bat.
The center fielder has missed the Astros' last five games with a mild intercostal strain after feeling soreness during batting practice on Sunday in Anaheim.
"We're going in a really good direction," Gomez said. "I feel really good, I seem to be feeling better. I'm more positive and happy because the first two days I was angry .. about the situation."
Chandler Rome is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.