He found out about it while watching television Saturday before the team bus left for Fenway Park. Kline also put off surgery to repair for a tendon in the index finger of his pitching hand that's 70 percent torn, thinking he'd be on the roster.
Before the game, the Cardinals put right-hander Al Reyes on the roster instead. Kline said general manager Walt Jocketty informed him when the team got off the bus at Fenway Park and that manager Tony La Russa only shook his hand about 45 minutes later.
"I'm dumbfounded, shocked," Kline said. "You get to the end of the rainbow and there's no pot of gold for me. I could have had surgery a month ago."
The decision left Ray King as the lone left-hander in the bullpen.
"I feel worse for Steve than I do for us because we are going to make the adjustments to compensate and still find a way to win," La Russa said. "He would have been helpful, but you know, we'll do without him."
Pitching coach Dave Duncan said Kline wasn't 100 percent.
"At this level of competition, to try to compete at less than 100 percent is not fair to him, or to us," Duncan said.
But trainer Barry Weinberg said Kline's finger is no better -- or worse -- than it was when the postseason began.
"They didn't ask the doctors and they didn't ask me," Kline said. "They assumed it, I guess. They didn't say, 'Steve, can you throw?'"
Kline thinks maybe the move was a sign that the team doesn't want him back. He can be a free agent after the season.
"I'm guessing," he said. "But that's the way it looks. It's ignorant."
The Cardinals also left 15-game winner Chris Carpenter off the roster. He had two successful bullpen sessions earlier in the week in an attempt to come back from nerve damage to his right biceps on Sept. 18, but the team felt it was too much of a risk.
"We've been assured that medically he's fine and there'd be very little possibility of reinjuring his arm," Duncan said. "But the bottom line is it's been over a month now that he's not been in any competition. I don't think two bullpens is a true test of whether or not he'd be ready to pitch."