The Boston Red Sox, Philadelphia Phillies and Detroit Tigers -- three very talented and highly touted teams -- have all sustained major injuries this season. Players such as Chase Utley, Dustin Pedroia, Magglio Ordonez and Carlos Guillen are all out of the lineup for various stretches of time.

But the Red Sox, Phillies and Tigers have managed to remain in contention without their lineups' linchpins. Currently, Boston and Detroit sit only five games out of a playoff spot -- the Red Sox in the wild card; the Tigers in the AL Central -- while Philadelphia is far from out of it, resting 2½ back in the wild card and 3½ in the NL East.

When I was a manager, I would look at my roster -- both Triple-A and major league -- and make a concrete plan on how to deal with potential injuries. Preparation for various scenarios is as big a part of the game as anything. And with Saturday's trade deadline so close and so much being discussed, there are various scenarios in play.

Still, there are some situations you'd rather not deal with. Boston, Philadelphia and Detroit are faced with one of those situations -- trying to replace players you have built your team around.

Now the job of these teams' managers and general managers is to get a timeline for the return of their players. From there, they need to examine whether a potential trade can replace or supplement the talent that's missing.

But when you're missing a star player, this process becomes a crapshoot.

All of these teams are built to win now. They have their eyes set on the 2010 World Series title -- not next year's. Of course, to trade for a proven player, these teams will have to give up prospects, mortgaging a slight part of their future. In the end, I don't think Boston, Philadelphia or Detroit would mind trading assets away before Saturday's deadline passes, as long as they acquire the right piece to their puzzle.

This is where the crapshoot comes in: No one -- not me or the managers and GMs -- knows whether that perfect piece is out there. These three teams are encompassed by equally complex and unique situations, only one of which is the future health of their star players.

Every clubhouse, every roster is different, and that's why so many of these trades end up being inconsequential. Some players just don't fit with a particular team's personalities. I have managed for more than 20 years in the major leagues and Japan, and I can't remember a single trade that put my team over the top.

A manager's job is to build a team from day one -- a team that doesn't rely on any one individual. The Tigers, Red Sox and Phillies are run by some of the best managers in the game -- Jim Leyland, Terry Francona and Charlie Manuel. They understand that a team's bench is just as essential as its stars.

That's why you don't see any of these teams in panic mode. They're simply looking for ways to improve their clubs, and whether they do that via a trade remains to be seen. You can tell Philadelphia, Boston and Detroit all have the attitude that they can win without their stars -- and that's a great quality for a club to have.

Successful teams never think they need another piece to make a playoff run, and it's the manager's job to establish that mentality in the clubhouse.

Bobby Valentine is an analyst for "Baseball Tonight."

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