"I think the reality is we gave him all of last year and three starts this year," general manager Jeff Luhnow said. "He deserved all that opportunity because he was good for us in 2012, but quite frankly we feel like at this point a change of scenery may be in the best interest of both Lucas and the Astros. Whether that means with another club or Triple-A, it's not something we feel like we can continue to do in Houston at this point."
Harrell told MLB.com it's probably time to move on, though the Astros could still wind up sending him to Triple-A.
"I was definitely surprised," he said. "I kind of saw it coming a little bit. Just in my starts, there was a ball off the wall here and plays here or there where it could have been a lot different. But they've got their plans and I understand that. I think it's best for both parties to kind of go their separate ways."
Manager Bo Porter said Harrell could benefit from going elsewhere.
"Sometimes situations run [their] course," he said. "Lucas Harrell is a Major League pitcher and we wish him nothing but the best. At the same time, sometimes a change of scenery is probably the best for a guy, and that's the point we got to as an organization."
Brian McTaggart is a reporter for MLB.com and writes an MLBlog, Tag's Lines. Follow @brianmctaggart on Twitter. This story was not subject to the approval of Major League Baseball or its clubs.