KISSIMMEE, Fla. -- Who's on first? That's the question just about every Astros fan wants to know as pitchers and catchers reported to Osceola County Stadium today for the start of Spring Training. The immediate answer is there will be a lot of guys on first during the month of March, but who will be standing there on Opening Day remains to be seen.
Will it be slugger Jon Singleton, A.J. Reed (the team's No. 4-ranked prospect), the intriguing Tyler White or the versatile Matt Duffy? Or will be it be a free agent who's currently at home looking for a job? The Astros have six weeks to sort it out, and expect them to use as much time as necessary to do so.
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There are other questions, too. Will it be Scott Feldman or Mike Fiers in the fifth spot in the rotation? Who will win the backup catching job? Will 2015 American League Rookie of the Year Award winner Carlos Correa take his game to another level?

The Astros, coming off their first playoff berth in 10 years, will have 61 players in camp by Tuesday, when the full squad is scheduled to hold its first workout. The expectations will be higher than they've been in Kissimmee in quite some time.
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"I think it's going to be a pretty focused camp," general manager Jeff Luhnow said. "We know what our objectives are this year, and that's a little different than maybe years past. Obviously, we always want to win as many games as possible, but having been to the playoffs and expecting and desiring to get back, we're going to be very focused on the goal at hand. I think we're still going to have a relaxed hand, but it will be serious and focused."
Here are three questions that must be answered this spring:
1. Who will start at first base?
There's a chance that Houston's Opening Day starter at first base isn't yet in camp. The Astros could still sign one of the remaining free agents, a group that includes Pedro Alvarez and Justin Morneau, if they don't like what they see from their internal candidates. Reed, the left-handed slugger who led the Minors in homers and RBIs last year, is likely the first baseman of the future, but he'll need to prove he can hit left-handed pitching and has yet to take an at-bat in Triple-A.
Singleton has crushed Triple-A pitching but has yet to hit consistently in the Majors, so this could be his final shot to prove his worth with Houston. White has done nothing but put up amazing numbers. However, like the others, he is unproven at the Major League level. Duffy is the dark horse and might be a better fit in a utility role rather than as a starter.
2. What will the final two spots in the rotation look like?
The late-January signing of veteran Doug Fister gave the Astros a sixth solid option for the rotation -- assuming everyone stays healthy. Fister is coming off elbow issues last year, and Feldman missed September following a shoulder sprain. Then there's Fiers, who has electric stuff.
Both Feldman and Fiers have pitched in the bullpen before, and both could be used in long relief. Whatever the case, Houston is in much better shape than the club was a year ago, when it opened the season with Roberto Hernandez as the fifth starter.
3. Can the Astros handle expectations?
Most experts believe the Astros are one of the top teams in the AL, and one that should make a push toward the playoffs. Last year, they come out of nowhere with no pressure on their backs for much of the season and were one of baseball's feel-good stories. This year, things are different. People expect them to win and compete, and that's going to be a first for many of the players. The pressure is real. The good news for Houston is manager A.J. Hinch always knows how to have his team in the right state of mind for any situation. How will the Astros respond in 2016?