Edwin Jackson has pitched better than any reasonable expectation. His emergence has created a conundrum for Cardinals GM John Mozeliak. How does he build the 2012 Cardinal rotation?

A quick look at next year’s rotation shows four of the 5 slots already filled.

• Kyle Lohse is under contract and will make $11.875M.
• Jake Westbrook is under contract and will make $8.5M.
• Jamie Garcia is under contract and will make $3.25M.
• The Cardinals announced last week they will pick up Adam Wainwright‘s 2012 and 2013 options. Wainwright will work for $9M in 2012.

The two most likely pitchers to take the last slot are Jackson and Chris Carpenter. Jackson is a free agent at the end of the season. St Louis holds a club option on Carpenter, who they can either retain for $15M, or buy out for $1M.

Does Mozeliak sign Jackson, or pick up Carpenter’s option?

The Case for Carpenter. This is Carpenter’s eighth year in St Louis. His previous seven season run has been one of the best in baseball history. His 141 ERA+ average for his age 29-35 seasons is the tenth-highest since 1901. You may have heard of the guys ahead of him. He won the Cy Young award in 2005 and finished in the top 3 in CY voting on two other occasions (2006, 2009). Chris Carpenter has had a fabulous career with the Cardinals. He is, however, 36 this season, and has the well-documented history of arm trouble. Basically retaining Carpenter becomes a loyalty question, and a gamble. Does St Louis reward him for his years of superior service? How many pitches does he have left in that right arm?

The Case for Jackson. Jackson throws hard, averaging a mid-90s fastball. He gets a lot of ground ball outs, but also gives up a lot of line drives. His FIP- numbers are below average the past 3 seasons. Out of curiousity, I ran some numbers through Baseball Reference to see how Jackson’s career to date measures up historically. For those comps, I looked at players 28 or younger as of 30 June 2011, who have started 80% of their games (Jackson’s started 85% of his), thrown more than 1000 innings, have at least 100 decisions, and an ERA greater than 4.25. You can find the complete list here. It’s a pretty unremarkable set of names, and none of the guys on it became elite pitchers.

Jackson’s past performance does not prognosticate to a lot of future success. He likely will remain a slightly below average major league pitcher. Then again, Carpenter was 49-50 when he came to St Louis from Toronto and look how that turned out.

Politics. The elephant in the room listening to this discussion is, of course, Albert Pujols‘ impending free agency. Most (this writer included) think the Cardinals will have to break a bank to retain Pujols in 2012. The amount of money it will likely take to re-sign the first baseman – widely expected to be north of $25M a season – may necessitate declining Carpenter’s option and using that $14M to pay Pujols.

The other issue is the Colby Rasmus trade. If Mozeliak lets Jackson walk away, he will have traded an elite, young prospect playing a premium position for a left-handed relief pitcher (I have assumed that Octavio Dotel and Corey Patterson do not remain with the club past this season). That will not sit well with the fan base, nor should it. The Cardinals will have sold Rasmus for pennies on the dollar.

The four options open to Mozeliak are:

1. Pick up Carpenter’s option, wave good-bye to Jackson;
2. Decline Carpenter’s option, sign Jackson to a new deal;
3. Decline Carpenter’s option, try and re-sign him to a new deal at a lower price, let Jackson go;
4. Decline to sign either, insert someone from Memphis into the Cardinal rotation, use the money saved to sign other free agents.

It is a tough choice. I do not envy Mozeliak. Cardinal Nation looks forward to how this will play out.

Mike Metzger is a life-long Cardinals fan who currently blogs about the San Diego Padres. Follow him on Twitter @metzgermg.

The St. Louis Cardinals have more than one contract concern going into this season. This is the last guaranteed year of Chris Carpenter’s contract. The team does hold a $15 million option for 2012, with a $1 million buyout.

Carpenter, who will turn 36 in April, has already stated he is not concerned with his contract status. But regardless of how the Albert Pujols saga ends for the Cards, $15 million is an awful lot of money to pay a 37 year old pitcher with an injury history as checkered as Carpenter’s. If the Cards do end up signing Pujols, it does not seem even possible they could afford to pay Carpenter that kind of money.

The easy answer, of course, would be for the Cards to decline Carpenter’s 2012 option and re-sign him for more money spread over another year or two. Think two years at somewhere in the $8-$11 million range annually, and maybe an option year. The numbers are hypothetical, of course, and would be based on a number of variables. And it also hinges on just how long Carpenter wants to extend his career, let alone his time as a Cardinal.

But there is another scenario in play here. Could the Cardinals actually trade Carpenter this season?

It sounds ridiculous and blasphemous, and I hate even bringing it up. But let’s say the NL Central is just as tough as some think it could be. Maybe the Cards sustain a major injury to one or two key players; it certainly happened last year and could happen any year. Some combination of those two forces would easily make things difficult for this team to compete in 2011. If the Cards find themselves out of the race early, they could turn into sellers at the trade deadline. And if Carpenter is healthy and producing, he would be as attractive a target as any team in contention could hope for. He is talented, he is a fighter, and he is a winner. A team with deep pockets who needs an extra bump for the playoff push (think New York Yankees) would snatch up Carpenter in a heartbeat if he became available.

Not that such a move is likely. Carpenter is still widely considered the co-ace of the Cards pitching staff with Adam Wainwright. He is a leader in the clubhouse and on the field. He is a core player on this team, and even if the Cards were forced into a position to move him they would almost certainly make the other team overpay. But it does add another layer of intrigue to a season that is shaping up to be pivotal for the future of the entire franchise in a number of ways.

Yes it would take the perfect storm of suck for the Cardinals to need to trade Carpenter this season. If the Cards are successful throughout 2011, all of this is moot until next off-season. But it is much less far-fetched to think he could be playing somewhere else by the start of the 2012 season, especially if escalating payroll becomes a concern. And as other contracts close in on expiration—namely those of guys like Wainwright and Yadier Molina—these decisions will only become tougher to make.

Chris Reed is a freelance writer from Belleville, IL who also writes about the Cardinals for InsideSTL Mondays and at Bird Brained whenver he feels like it.