Back then, the ramifications of switching leagues were still off in the distance, months away from becoming problems. The Astros still had to finish their 51st year in the National League, after all.
But with three games remaining as an NL team, Astros players and officials are starting to consider exactly what needs to be done before Houston takes the field as an AL club on April 2 at Minute Maid Park.
"There are really compelling reasons to get excited about the future," general manager Jeff Luhnow said. "New look next year, new division, new league, new staff. There's a lot of reasons we're excited."
The Astros moved quickly on the first order of business, finding a full-time manager. Luhnow considered the league differences during the interview process that led to the choice of Nationals third-base coach Bo Porter, but he said the switch wasn't a huge factor.
Moving from the AL to NL would be a bigger deal to Luhnow, because NL managers need to understand specific concepts like double switches.
"He's going to be a very smart manager," Luhnow said. "He's going to figure it out very quickly."
The Astros want to work with Porter on the formation of the coaching staff, but that process won't start until the Nationals finish their run in the postseason.
"We need to make sure that we surround Bo with a staff that has all the capabilities -- whether that's experience in the American League, infield experience, pitching experience etc. -- to create the best staff in baseball to support the best young talent in baseball," Luhnow said.
With a manager hired, the front office will now decide how it wants to address the fact that the Astros will need a designated hitter for most of their games next season. Luhnow could add a prolific hitter to the roster via free agency or plan on filling the position internally, or even some combination of the two.
"We'll be looking at every opportunity to get a guy in the lineup that can help us produce runs," Luhnow said. "It's a high-scoring environment in the American League, and we're facing not only teams with good lineups but good pitching, and we have to be in a position to compete more than we were this year. We hit more home runs this year than we did last year, and we have to hit a lot more home runs next year than we did this year."
The DH rule will also affect the pitching staff. The move means they'll be facing a more potent lineup.
Rookie Lucas Harrell, who made three starts for the White Sox in 2010, said the prospect of facing nine professional hitters instead of eight and the pitcher means he must stay even more locked in and focused.
"You can kind of take a little bit of a breath in the National League, with having the pitcher up," Harrell said. "The American League's no joke. You have the DH. He gets paid strictly to hit homers and drive guys in, so he's usually one of the better hitters on the team."
NL pitchers can pitch carefully to hitters in the bottom of the lineup, knowing that the pitcher will hit. That won't be an option next year.
Harrell brought up a hypothetical situation in the NL where the eighth hitter comes up with two outs. A walk isn't terrible in that situation because the pitcher is on deck. Harrell can pick his spots, and if the hitter doesn't bite, he takes a walk and the pitcher comes to the plate.
"In the American League, that doesn't happen," Harrell said. "You walk that guy and the next guy that comes up is a regular hitter. He gets a base hit and now you've started a big inning with two outs. You've got to be careful."
Another ramification of the move for Astros pitchers: they won't get the opportunity to show off their swings as often. Harrell, a career .150 hitter, said he enjoyed hitting, but won't really miss it.
And then there's the fact that the rebuilding Astros will join the powerful AL West, home to the Angels, Rangers, A's and Mariners. That means new road trips and the need to scout AL pitchers and hitters more frequently.
Former Astros second baseman Craig Biggio said fans shouldn't be too concerned about the move.
"The great thing about Astros fans and this city is we are resilient," Biggio said. "Hey, this is what it's going to be. We're going to make the best of it and go out there and try to compete in the American League West."
Luhnow understands that fans will feel nostalgic about leaving the NL, but he also urges them to look forward to new rivalries and the chance to see more AL teams at Minute Maid Park.
Larry Dierker, a former player, manager and broadcaster for the Astros, thinks next year's schedule will continue to blur the lines between the leagues anyway. With 15-team leagues, Interleague Play will happen nearly every day of the season.
"The only major difference is the DH," Dierker said. "I'd prefer not to have it, but I'd say, 'Get over it.' It will still be baseball, and it will still be fun."
Clark Goble is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.