The St. Louis Cardinals came into spring training this week with a number of questions about their starting rotation.

Who will win the fifth starter spot? Who will replace the injured Chris Carpenter?

Then a new guy showed up at camp—a skinny fellow with a small goatee. Well, he wasn’t a new guy, but he may as well be.

When Lance Lynn showed up almost 40 pounds lighter than when he left St. Louis in October, he probably didn’t know that his new, leaner physique would be the first big story of the spring.

Lynn, who filled in for Carpenter, couldn’t have asked for a better 2012. His 18-win season over 29 starts earned him his first All-Star berth. He also managed to rack up 180 strikeouts—not bad for a young man in his first year as a starter.

Late in the season, a few hiccups jeopardized his position and landed him a brief bullpen stint. He came back strong, but struggled again in the postseason.

Lynn appears to have returned ready to make a statement that last year was not a fluke.

What will this new physique mean for his mechanics?

Until he takes the mound, we won’t know the full effect on his velocity. While velocity can take a hit with weight loss, the increased endurance, with any luck, will more than make up for it.

He’s an intelligent pitcher, and having a catcher like Yadier Molina to help keep him on the right track has been invaluable.

Lynn will have the entire spring to show why he deserves to be a starter again in 2013, and I have little doubt that’s where he will wind up when all is said and done.

Something that has always intrigued me about Lynn is how he gets dialed in. The key to getting past Lynn is to strike early. Through his first 15 pitches, batters hit .333 against him, but the numbers fall off dramatically from there.

Pitches 16-30: .231
Pitches 31-45: .255
Pitches 46-60: .214
Pitches 61-75: .133

Once Lynn settles in, he can dominate. Late in the 2012 season, as he grew heavier, those numbers slipped a bit.

The hope is that he will see a serious increase in stamina and endurance that will bring him back to that form that helped carry the Cardinals through the majority of the year.

He showed a ton of promise in 2012, with signs that he has what it takes to be a long-term big league starter.

Lynn’s four-seam fastball, his main pitch, clocks in the mid- to upper 90s. He also throws a nasty changeup in the upper 70s to lower 80s, which gives him a fantastic ability to keep hitters on their toes.

Throughout the 2011 World Series, then-manager Tony La Russa relied heavily on Lynn as a powerful bullpen arm. At 23, Lynn was lights-out in the eighth inning of Game 7 of the World Series.

That’s about as tough as tests can get.

Starting now he has another test—showing the management that what they got from him in 2012 was not a fluke. He filled in for Carpenter admirably once before; now he has the opportunity to own that slot in the rotation.

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