Chris Carpenter back at Cardinals' camp

St. Louis pitcher Chris Carpenter has returned to the Cardinals' spring training camp, with manager Mike Matheny still unsure when his ace will be back on a mound.

St. Louis pitcher Chris Carpenter has returned to the Cardinals' spring training camp, with manager Mike Matheny still unsure when his ace will be back on a mound.

Carpenter, who has yet to pitch in a spring training game, underwent four days of tests last week in St. Louis to determine the cause of a nerve ailment that has weakened his throwing shoulder. Matheny thinks the right-hander will have to rest.

''I've been there before,'' Matheny said Monday. ''When I had the concussion stuff they were flying me all over the country trying to get me to this specialist and that specialist, and sooner or later I just said: Enough, hopefully you guys have the information you need. He understands the process, but it's kind of grueling as far as the poking and prodding.''

The 37-year-old has not faced hitters since batting practice on March 3. A bulging disk in his neck originally was thought to be the cause of the problem.

The 2005 NL Cy Young Award winner was 11-9 last season, then went 4-0 in the postseason as the Cardinals won the World Series. He threw 273 1-3 combined innings between the 2011 regular and postseasons.

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