With that in mind, here's a look at some of the players and teams facing the most pressing health questions over the next seven weeks.
Derek Jeter and Mariano Rivera, Yankees: No biggie, just major injuries to the two faces of the franchise.
Rivera blew out his knee early last season but by all accounts has more or less recovered. He's targeted being on the roster on Opening Day, and barring any significant setbacks, that should be the case. The Yankees are somewhat less equipped to deal without Rivera this season than they were in 2012 due to the departure of Rafael Soriano via free agency. Any time without Rivera would weaken what should be a strong but thinner relief corps.
Jeter is the bigger question, in terms of both his health and of what the Yanks would do without him. All of the recent reports have been glowing as he attempts to recover from a broken left ankle, but he is 38 and his range was already declining. Moreover, that was a major injury he sustained at the end of the American League Championship Series.
To top it off, New York is already doing without Alex Rodriguez on the left side of the infield. A Jeter absence would probably mean a steady diet of Eduardo Nunez, a capable enough hitter but no match for what Jeter offered in 2012. Jeter seems to be feeling good now, but the question is how he will hold up to the daily strain of working out and playing.
Carl Crawford and Matt Kemp, Dodgers: For one of baseball's biggest-spending teams, the Dodgers have an awful lot of questions. It starts with their lineup, as two of their three or four most important players have uncertainty following them.
Crawford underwent Tommy John elbow surgery in August, and he's on a throwing program at this point. For all the talk of him as a bust in Boston, he actually hit pretty well in 2012 before getting hurt. If he can even repeat that performance, he'll be a boon for the Dodgers. If he can't go, it likely will open the door for Jerry Hairston Jr. or Skip Schumaker.
Schumaker is also at the top of the backup-plan list for Kemp, who was bothered by myriad injuries last season. The one that bled into the offseason was in his left (non-throwing) shoulder. Though he's expected to be fine, he wasn't the same player in the second half last year than he was when healthy early in the year. He shouldn't be unavailable, but it's to be seen just how sharp his form will be.
Rafael Furcal and Jaime Garcia, Cardinals: A pair of precious throwing arms will go a long way toward determining the Cardinals' success in 2013. Both Furcal and Garcia eschewed surgery, and the club is seriously hoping they were right to do so.
Shortstop Furcal is one of the most essential Cardinals, Pete Kozma's spectacular late-season surge aside. The backups include Kozma, Ronny Cedeno and Ryan Jackson, none of whom can hold a candle to a healthy Furcal -- assuming we ever see such a creature again. The switch-hitter is hoping that rehab was enough to repair the damaged ulnar collateral ligament in his right elbow. The official word is that he'll be fine this spring, but it's an open question until he starts playing games.
A similar statement can be made about Garcia, who chose not to have surgery on a troublesome left shoulder. His importance was ratcheted up several notches with the announcement that Chris Carpenter is expected to miss the year. One youngster is already likely to be in the rotation -- presumably Joe Kelly or perhaps Shelby Miller. If Garcia isn't good to go, it could mean two first- or second-year pitchers in the starting five.
Jose Bautista, Blue Jays: For all the work the Blue Jays did this offseason, their best and most important player was already on the roster. They remade their rotation, including adding a No. 1 starter in R.A. Dickey. On the offensive side, though, the players they added were complementary. By far the most essential hitter in the lineup is Bautista, and he is recovering from an injury to the scariest area for a hitter: his wrist. Bautista underwent surgery on the joint in late August and has been swinging since December. By all accounts, he is expected to be ready for the season, but his status will remain somewhat in question until he displays full effectiveness and it is seen how much of his power he will retain.
The backup plan might involve large doses of Rajai Davis, so it's imperative that the Blue Jays have Bautista at full strength.
Brian McCann, Braves: A reasonable read on the Atlanta catcher is that he won't be ready for Opening Day. He's recovering from surgery on his right shoulder, which is both his throwing shoulder and his front shoulder as a left-handed hitter. That's a pretty key area, and his recovery will largely determine how much of his pre-2012 form he can regain.
McCann likely won't be involved in games at all early in camp. Once he starts getting into games, he might be eased in. The Braves would be wise to be cautious with a player who figures to be a central part of their push for a division title.
McCann's situation is magnified because the Braves lost his backup, David Ross, to the Red Sox via free agency. Instead, Gerald Laird is now the primary Plan B. Laird is a solid defender but nowhere near McCann's equal with the bat. McCann will be missed for as long as he's out.
Others to watch: Matt Garza, Cubs; Ryan Madson, Angels; Wilson Ramos, Nationals.