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The St. Louis Cardinals are embroiled in their own instance of Lynn-sanity.

As it commonly goes in sports, Cardinals new starter Lance Lynn is another prime example of the "next man up" scenario: when one player goes down, another fills the gap.

The hole Lynn filled is more like an abyss.

Lynn was better known for a bullpen err during the 2011 World Series, but now he's currently regarded as the Cardinals' most reliable pitcher. The converted reliever has taken over the rotation spot for 2005 NL Cy Young Award winner and two-time champion Chris Carpenter, and he said his new role would be a challenge.

Cardinals first-year manager Mike Matheny touched on that.

"We all understand the importance of Chris Carpenter and how badly we want him to get right," Matheny said. "But when the game deals you what it deals you, you hope somebody steps up. And to see (Lynn) step up is gratifying to those guys in (the clubhouse)."

With a healthy mix of fastballs, curves, a cutter and a change-up, Lynn pitched his way to a sizzling 6-0 record through his first six outings, receiving a hefty amount of run support. The Cardinals averaged seven runs in that stretch and Lynn pitched no less than five innings each times.

Lynn, though, tasted defeat for the first time this season in Sunday's 7-4 loss against the Atlanta Braves and couldn't help his club avoid a sweep at Busch Stadium. Lynn pitched well in the loss, surrendering a season-high three runs in six innings with seven strikeouts. He threw a season-high 121 pitches and struck out seven for the fourth time, and was trying to become the first pitcher to win seven straight games to open a season since Brandon Webb won his first nine with Arizona in 2008.

Opposing hitters have taken notice of Lynn, too. Milwaukee Brewers slugger and reigning NL MVP Ryan Braun did so early on this season.

"I was surprised that somebody could transition from the bullpen to a starter and maintain his stuff," Braun said after Lynn's first start in April. "His velocity was consistently in the mid-90s. He has really good command of his fastball to both sides of the plate, and last year he didn't throw much of his slider/cutter pitch, whatever he was throwing today. I was impressed."

Despite the first loss, Lynn, who has made nine career starts in 25 appearances, leads the National League with six victories and leads the Cardinals with 44 strikeouts. The right-hander will have the next few days off before getting back to work and should be in the St. Louis rotation at least until after the All-Star Game.

That's when Carpenter is expected to return from a bout of nerve irritation in his right shoulder. The Cardinals don't anticipate having Carpenter back before the break since he hasn't thrown a baseball in about two months.

Carpenter must pass a rigorous strength test before resuming throwing duties, and it will take about four to six weeks for the former staff ace to build his arm back to normal. Of course, there could be stumbling blocks along the way and it all boils down to how Carpenter's golden right arm responds to the treatment. So basically there's no need to rush him back just yet.

"I want my shoulder to work right," Carpenter said. "I want to be able to throw properly. I don't want my arm getting numb. I don't want to get weak. I want to feel normal and then move on from there."

Whether the Cardinals can move on with Lynn back in the bullpen is a hurdle they will have to clear when the time comes. But by then, Lynn could still be among the league leaders in wins.

Do we see a six-man rotation in the Cardinals' future with Lynn, Carpenter, Kyle Lohse, Jake Westbrook, Adam Wainwright and Jaime Garcia?

We shall see in early July.