And the Dice-K saga, 2010 version, begins.

Before being required to throw his first spring training pitch, Matsuzaka has been shut down.

But the righthander has been shutdown as a precaution. The Red Sox think the injury is just the result of overwork and not due to some specific incident.

“He played catch on Friday and was thinking about throwing a pen and said he felt it a little bit in his mid upper back and decided not to throw the pen,” Epstein said. “Our trainers took a look and we just decided, ‘Hey, let’s slow this down and do it conservatively.'”

Overwork? And here we are with no World Baseball Classic to blame. The reliability of Dice-K being part of the rotation has to be in question. Considering the history of Dice-K and “hidden injuries” I think Lackey, Beckett, Lester, Buchholz and Wake is looking like a pretty good starting five.