In a perfect world, none of the 30 teams in Major League Baseball would have any lingering question marks in the home stretch to Opening Day on March 28.

But when has the world ever been perfect?

We're here to look at each team's biggest unanswered question as a new season looms. Some are as simple as which players are going to fill which roles. Others concern the health and/or playing ability of star players. Still others concern possible roster construction faults.

We'll go in alphabetical order by city.

Arizona Diamondbacks: Who's Catching?

The Arizona Diamondbacks have yet to decide whether Archie Bradley, Greg Holland or Yoshihisa Hirano will be their closer, but that's a competition for a mere label.