In exchange for the speedy Bourn, the Astros received outfielder Jordan Schafer from the Braves and three Minor League pitchers -- left-hander Brett Oberholtzer and right-handers Paul Clemens and Juan Abreu. Schafer is on the disabled list with a broken finger and will be examined by team doctors on Monday in Houston. The Astros also sent cash in the deal to the Braves.
The Astros are trying to trim payroll in advance of the team's impending exchange of ownership, and they continue to bring in young players in an effort to restock a farm system that's among the weakest in baseball. Houston has acquired 10 players in the past two weeks by trading Pence, Bourn and infielder Jeff Keppinger, who was sent to the Giants on July 19.
"As was the case with Hunter Pence, this is not the position that we want to be in to have to move not only outstanding players, but outstanding people," Astros general manager Ed Wade said. "But time and circumstance dictates that we have to be able to build the type of depth in the system that at some point in time will allow us to have sustained success here."
Astros players were still trying to wrap their minds around the trades upon arriving at Miller Park on Sunday.
"This is crazy," third baseman Chris Johnson said. "First it was Keppy and then Hunter and now Michael. At one point, that was our 1-2-3 in our lineup. Just the same thing as when Hunter went. We've got go step up and move on and just know that our owner and our GM have plans for us in the future, and that's what we're building towards."
Bourn, acquired by the Astros from the Phillies after the 2007 season in the Brad Lidge deal, was having his best year, batting .303 with 39 steals in 105 games. A Houston native, Bourn told MLB.com via phone Sunday he wasn't surprised he was traded.
"They're trying to rebuild and reload," Bourn said. "I understand that. There are no hard feelings involved. I knew what was going on. I told everyone else when I saw Hunter go, 'There might be a possibility I'm going, too.' That's a part of what happens sometimes."
The Astros entered Sunday with the worst record in baseball (35-72) and fielded a starting lineup that included two players -- second baseman Jose Altuve and left fielder J.D. Martinez -- who were in Double-A for most of this season. Martinez was called up to replace Pence.
The trades of Bourn and Pence -- the Astros' two best players and most popular players -- have stunned the fan base.
"I can understand the level of concern and disbelief maybe that exists out there," Wade said. "It's clearly understood, and these are not things that we do easily, but we've got to do the things that point us in the direction where we're not going through the types of seasons that we're going through right now -- and a little bit of what we've gone through in the past."
Schafer, 24, is expected to take over in center field for Bourn when he returns from the disabled list, which could be in about 10 days. A left-handed hitter, he split this season between Triple-A Gwinnett and Atlanta, hitting .240 with a home run, seven RBIs and 15 steals in 52 games.
Once considered the top prospect in the Braves' system, Schafer has seen his career stall as he has dealt with a left wrist injury and a banned-substance suspension over the past three seasons. The Braves were forced to call Schafer up from Gwinnett in late May, and he had spent most of the past two months as their starting center fielder.
Schafer was placed on the disabled list after injuring his left middle finger on a headfirst slide last week in Colorado.
"It hurts, no doubt," Schafer said of the trade. "This is the only place I've known, so it hurts. I thank the Braves for staying behind me the entire time with everything I've been through. They've been great for me. I was comfortable here, but at the same time, I'm excited to go over there. Any time you get traded, the team obviously wants you. I'm excited to go over there and start fresh and try to start winning up there."
Abreu, 26, was 4-2 record with one save and a 2.25 ERA in 41 relief appearances for Gwinnett this season. He's limited opponents to a .193 average, including a .167 average by right-handed hitters, and has fanned 68 hitters in his 48 innings pitched.
"We see him as a power arm, power fastball, power breaking ball, and somebody that should factor into the competition for a bullpen spot for us no later than next Spring Training," Wade said.
Clemens, 23, had a 6-5 record and a 3.73 ERA in 20 starts for Double-A Mississippi this season. The 6-foot-4 right-hander was a Southern League All-Star this season and was originally selected by Atlanta in the seventh round of the 2008 Draft.
Oberholtzer, 22, went 9-9 with a 3.74 ERA in 21 starts for Mississippi this year, making the Southern League All-Star team. The Astros envision Oberholtzer and Clemens as middle-of-the-rotation starters in the near future.
"To get two starting pitchers of this magnitude at Double-A, close to the big leagues, makes sense, along with the center fielder," Wade said.
This is the second straight year the Astros have made two significant trades at the Deadline. Last year, they sent Roy Oswalt to the Phillies and Lance Berkman to the Yankees within a matter of hours and acquired five players, including pitcher J.A. Happ, reliever Mark Melancon and first baseman Brett Wallace.
The club started four rookies for most of the second half of last season and figure to give Altuve and Martinez plenty of playing time this season. And there should be plenty of opportunities for prospects to move through the system in the next few years.
"We inherited a pretty barren farm system, and we're paying the price for it right now," said Wade, who was hired late in the 2007 season. "Part of the price that we're paying for it are the good, established players we have here have to be moved along so that we can build multiples of prospect talent in the system to get to the point where it needs to be so the next group of guys hopefully are hitting on all cylinders, and we're able to retain those players and sustain a level of success that our fans deserve here."
Brian McTaggart is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.