The St. Louis Cardinals had already called RHP Chris Carpenter‘s season over. He was shut down for the season by surgery to correct his thoracic outlet syndrome.

The idea was that hopefully by spring training he would be back to his old self following an intense regimen this winter that would have him presumably back to normal.

That was the plan less than three weeks ago. Plans change.

Once Carpenter was first able to begin resuming baseball activities, it felt good. He threw more and kept feeling good—a sensation he hadn’t had in quite some time.

He felt so good, in fact, that rumors began to fly about whether he could throw again this season.

After several simulated games and bullpen sessions, Carpenter on Monday was believed to still be a simulated start away from making his return to the big leagues.

As Cardinals fans have already learned in the Carpenter capers of 2012, plans can change.

Given the lackluster performance by LHP Jaime Garcia on Monday evening, plans need to change.

Follow the break for five reasons why the Cardinals must activate Carpenter for Saturday’s start in Los Angeles.

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