Baltimore sent outfielder L.J. Hoes and left-handed prospect Josh Hader to the Astros for Norris, a 28-year-old right-hander whose $3 million salary was the highest on a roster filled with young players.
"We've been trying to bolster our pitching staff, and in Bud Norris we have a pitcher that can give us some quality innings," said Dan Duquette, Orioles executive vice president of baseball operations. "He's been a very dependable pitcher for Houston over the course of his career."
The Astros and Orioles were in the middle of a three-game series as the non-waiver trade deadline expired. So Norris packed up his gear and made his way a few hundred yards through the bowels of Camden Yards to the home clubhouse to begin the next chapter of his big league career.
In the process, he left the team with the worst record in the majors to a club seeking a second straight trip to the playoffs.
"I'm excited for the future," Norris said. "I pitched my way into this situation to be traded and help out a team. This (Baltimore) team is a young club, they know how to contend. They had an amazing year last year. I just want to be any piece of the puzzle I can to help this team keep pushing to the World Series."
In his fifth big league season, Norris is 6-9 with a 3.93 ERA in 21 starts this year. He has a lifetime record of 34-46 and is under team control through 2015.
"He's competitive, a strike-thrower. He has a nice approach," Orioles manager Buck Showalter said. "He's been healthy, and he competes. I like that fact that he gets after it. He'll have some challenges ahead of him, but he's not the only guy that's got to do well for us to be more competitive."
Baltimore began the day five games out of first place in the AL East and in the thick of the wild-card chase. Norris was the third pitching addition the Orioles have made via trade in July; previously they obtained Scott Feldman and Francisco Rodriguez.
"I really thought once they got Scott Feldman my chances went down," Norris said. "But obviously we got a couple guys now."
The Orioles said Norris would make his debut on Thursday against Houston. Scratched from his scheduled start Tuesday, Norris is ready to pitch for Baltimore.
"I'm pretty fresh," said Norris.
With Norris slipping into the rotation, Chris Tillman will move back a day and start Friday against Seattle.
Baltimore has not said who will pitch in place of Hammel, who was slated to start Saturday against Seattle. Hammel has a strained flexor muscle in his right arm and was placed on the 15-day disabled list Wednesday. He is 7-8 with a 5.20 ERA in 21 starts, but winless since May 27.
"Honestly, until the MRI comes back I don't know how to describe it other than that it's tight," he said. "Sometimes it feels like it grabs when I throw. It's not like a pinch, but I think tightness is the one thing we can label it as. It's not allowing me to fully extend when I pitch."
Hoes was one of the Orioles top prospects. A third round pick in 2008, Hoes was hitting .304 for Triple-A Norfolk before being recalled on Sunday by the Orioles.
He was in Baltimore's starting lineup Wednesday. Then, after the trade, Hoes was inserted into Houston's starting lineup.
"It's not every day that you show up to a major league ballpark and look at the opposing team's lineup and see someone in the lineup playing left field for that team, then an hour later he's been traded and is now on your team and is playing right field," Houston manager Bo Porter said.
For Hoes, the walk down the hall was bittersweet. He grew up in the District of Columbia and now lives in Maryland, so Baltimore was quite familiar to him. But in Houston, he will receive more playing time.
"I kind of got my dream come true the other day, getting to start for the hometown team," Hoes said. "Now, getting traded and going to the opposite dugout and locker room, I'm going to be able to make another start tonight and play against the Orioles. It's different. I never saw it coming, but it's part of the game, it's part of life."
For the Astros, the rebuilding process continues.
"Whenever you lose your opening day starter, and a guy that's been our best pitcher all year, it's definitely a blow to the ballclub," Porter said. "I think we have enough young pitching in our organization that we feel comfortable moving forward that we can replace those starts the rest of the year."