After adding Cliff Lee to a starting rotation that already included Roy Halladay, Roy Oswalt and Cole Hamels, the Philadelphia Phillies looked virtually unbeatable.
Then came spring training with injuries to Domonic Brown, Brad Lidge and, more significantly, Chase Utley, who could miss the first half of the season with a troublesome knee. That, coupled with the loss of Jayson Werth to free agency, could make the Phils' line-up vulnerable. Their pitching will be enough to win them the division, but not by as comfortable a margin as it seemed during the off-season.
If there is a team poised to make a run at the Phils, it is the Atlanta Braves who have a formidable starting rotation of their own. The offence is anchored by the veteran Chipper Jones, in probably his last season, and sophomore sensation Jason Heyward. A bullpen stocked with hard-throwing arms gives them an edge over the Phils.
If the Florida Marlins had not traded off Dan Uggla, their leading hitter, they, too, might have been a factor in the East. Josh Johnson is a legitimate No 1 starting pitcher and Hanley Ramirez, the shortstop, is among the game's most skilled players. But the bullpen is unsettled and line-up unproven.
This will be a difficult season for the Washington Nationals. They have two franchise players in Stephen Strasburg and Bryce Harper. But the former is out for the season with shoulder surgery and the latter is another season away from making an impact in the majors.
At least the Nationals have something to which they can look forward. That is not the case with the New York Mets, who are in legal and financial limbo, and whose chief spring accomplishments were the release of two overpriced and underperforming players.
• NL Central: Cincinnati endured some spring health issues for starting pitchers Johnny Cueto and Bronson Arroyo, but in a weak division, the Reds' powerful line-up will be enough to help them repeat as division champions.
Trading for Zack Greinke, a Cy Young Award winner, looked like a stroke of genius for the Milwaukee Brewers last winter. That was before Greinke broke a rib playing basketball, forcing him to miss the first month of the season. Spotty defence and uncertainty in the bullpen make the Brewers flawed.
The duo of Chris Carpenter and Adam Wainwright would have given the St Louis Cardinals the best one-two rotation punch in the division. But Wainwright is lost for the season after undergoing elbow surgery. It will also be fascinating to see how Albert Pujols's pending free agency impacts the Cards.
The Chicago Cubs were hoping that bringing back interim manager Mike Quade would help turn the club around, but in spring training they looked like the same old Cubs - fighting one another in the dugout and bumbling on the field.
The Houston Astros won their only National League pennant in 2005, but that now seems like a lifetime ago. And the string of 18 consecutive losing seasons will not be broken this year for the Pittsburgh Pirates, though Andrew McCutchen, Pedro Alvarez and Jose Tabata offer hope that it will not go on forever.
Ÿ NL West: The Phillies might have the game's best starting rotation, but the defending World Series champions San Francisco Giants can lay claim to the best home-grown rotation - and that is crucial, since the Giants' rotation is much more affordable. But can Madison Bumgarner, a revelation in the post-season last year, put himself in the same class as rotation-mates Tim Lincecum and Matt Cain?
The Colorado Rockies are top-heavy with stars, from Carlos Gonzalez in the outfield to Troy Tulowitzki at shortstop to Ubaldo Jimenez, the No 1 starter. That trio alone should guarantee that the Rockies will remain in contention.
The Los Angeles Dodgers are beset with ownership issues, clouding the franchise's day-to-day operation. Don Mattingly replaces Joe Torre in the dugout, and between some indifferent young stars and a questionable infield, Mattingly will have his challenges.
A year ago, the San Diego Padres were in contention for the division title until the last game of the season. After dealing off Adrian Gonzalez, their best player, they're likely to be out of the post-season picture far sooner.
Kevin Towers, the New Arizona Diamondbacks general manager, made overhauling the bullpen his first priority. But there is plenty more work to be done before the Diamondbacks are factors again.