Chris Carpenter's injury has created a huge hole in the Cardinals' rotation.
As good as the St. Louis Cardinals were in April (14-8) they were predictably just as awful in May (13-16) as numerous injuries have mounted for the team.
After looking every bit like the defending World Series Champions in the early going, they currently rest in third place behind the all-pitch no-hit Pittsburgh Pirates and the tough, but flawed Cincinnati Reds.
As GM John Mozeliak cast his lot with aging All-Stars Lance Berkman, Rafael Furcal and Carlos Beltran, it was clear the overall health of the roster would be the most important hurdle the team would face in 2012.
Here are the five most critical injuries St. Louis has had to endure so far.
The Cards have missed a veteran bullpen presence.
Critical to the Cardinals playoff run in 2011 was the acquisition of Octavio Dotel, who immediately became the veteran, high-leverage righty out of the bullpen they so badly needed.
Scott Linebrink was supposed to serve that role for the Cards' bullpen this year, but has yet to appear in a game for them as he deals with an inflamed shoulder that first cropped up in spring training.
Durable and serviceable throughout his career, Linebrink is close to starting a rehab assignment and the club hopes he can make a return some point in June.
A bullpen that has been gassed can't get his 35-year-old arm back soon enough.
Kyle McClellan's absence has left the club without a long reliever.
Cardinals' equipment manager Rip Rowan should stitch a white cross over a red patch to the uniform of Kyle McClellan, not just because McClellan (who is a native of St. Louis) is unfortunately injured, but also because he has been the Swiss Army knife of the Cards' pitching staff since 2008.
McClellan has the ability to pitch in any situation and has been particularly effective against lefties throughout his career—a .211 average allowed to southpaws to be precise.
A testament to his team-first attitude, McClellan volunteered to step into a starting role last year and finished with a 12-7 record while nearly doubling his average yearly innings load.
Though he was very effective early last year, he faded gradually as the innings caught up to him and it may have even served as the impetus for his elbow injury this season, where he has largely been ineffective and has now been shut down.
Marc Rzepczynski has been primarily tasked to fill this void as he has been billed as a lefty with starter-quality effectiveness to batters on both sides of the plate. However, he has clearly been exposed by right-handers (.297/.350/.568/.918) in 2012.
With McClellan, the team hopes that surgery is not needed and with 6-8 weeks of rest he may return late this year. Until then, the Cardinals will have difficulty finding such a diverse hurler.
Jon Jay was poised to become a core Cardinal in 2012.
While the Cardinals were doing everything in their power to coax a Hall of Fame career out of the enigmatic Colby Rasmus, all Jon Jay has done is carry a .303 batting mark over a full season and a half while bringing a solid glove to the Redbirds outfield.
As the Cardinals' regular center fielder, Jay seemed ready to blossom into a borderline All Star as he has batted .343/.395/.438/.833, even with some ineffective playing time after his shoulder injury which now has him sidelined.
With Jay out, Cardinals manager Mike Matheny has had to choose between offense (Carlos Beltran) or defense (Adron Chambers, Shane Robinson) in center. None bring the total package that Jay has on a consistent basis.
The Cardinals hope to have Jay roaming the Busch outfield well before the All Star break.
Lance Berkman seems more durable in the outfield than at first base.
Lance Berkman's stellar 2011 campaign was one of the biggest surprises of the season. He was by all accounts the Cardinals' MVP last year and the heart and soul of a laid-back, never-say-die clubhouse that just seemed happy to be playing baseball.
What did Berkman say minutes after World Series Game 6 was won by an 11th inning bolt off the bat of David Freese? He said he wished they could head back out to play Game 7 that night.
While Cardinal fans had more reasonable (actually, lessened) expectations for Berkman in 2012, he actually was carrying a very similar slash line in 2012 to what he had last year. So it seems that last year was not a fluke, but the continuation of a borderline Hall of Fame career.
So his absence from the clean-up spot in the lineup is a huge void the Cardinals must endure. At least for the first half of the season.
Luckily for all involved, Berkman did not need season-ending knee surgery and is expecting to make a definite impact on the Cardinals' fortunes after the All Star break.
Healthy or not, Chris Carpenter is the leader of the Cards' pitching staff.
This writer picked the Cardinals to finish third in the National League Central last year after Adam Wainwright was lost for the season to Tommy John elbow surgery.
When Chris Carpenter began the season 1-7 as he was bedeviled by mediocre run support and a leaky bullpen, that prediction seemed to be on track.
Then Carpenter got on track.
His final record of 11-9 in no way does justice to the heart he showed in battling back throughout the season, getting better and better, shutting out the Astros in the final game of the regular season and then beating Roy Halladay 1-0 in Game 5 of the NLDS.
So with so many question marks going into 2012, the last thing Mike Matheny needed was the absence of his ace. In the meantime, Lance Lynn has been more than the club could have hoped for and Adam Wainwright seems to finally getting over the post-surgery hump.
If Carpenter can return to the rotation in mid-season, it will bring a huge lift to a staff that has been dragged down by Bryan Westbrook and Kyle Lohse's regression to their career means and Jaime Garcia's own ineffectiveness that has led to a DL visit.
It's entirely possible that the second-half Cardinals could be healthy and ready to make another late-season run.