BOSTON - Thanks to the signing of Bartolo Colon and the unexpected contributions from Justin Masterson, the Red Sox would seem to have enough starting pitching to get themselves through the regular season.

The postseason? That could be another matter altogether.

From the time they discovered the severity of Curt Schilling's shoulder and biceps woes in January, the Sox weren't counting on him for much during the season. They held out some hope - and nothing more - that Schilling could get himself ready for the postseason. Even last October, pitching at far less than his best and with the aid of cortisone shots, Schilling managed to go 3-0 as the Red Sox again won the World Series.

Schilling's surgery yesterday, however, eliminated any possibility that he might contribute this postseason, leaving open the question: Do the Sox have enough experienced starting pitching to withstand three rounds of baseball in October?

In both 2004 and 2007, the Sox rode a powerful one-two pitching punch to titles. In 2004, the combination of Pedro Martinez and Schilling helped the franchise end its 86-year drought; in 2007, it was Schilling and Josh Beckett.

But who stands with Beckett this fall? Daisuke Matsuzaka has yet to fully earn the team's trust in big games. Last fall showed him to be susceptible to patient lineups that can extend his pitch count and limit his impact.

Colon has made it past the Division Series only once in his 12 major-league seasons and owns a rather ordinary 2-4, 3.61 ERA career postseason mark. In addition, given his elbow and shoulder issues the last two seasons and his two DL stints thus far this season, Colon's durability remains a question mark.

Tim Wakefield, famously streaky, had a fabulous first postseason as a rookie with Pittsburgh. Since then, his postseason ERA in a Red Sox uniform is 7.54.

That leaves Jon Lester, who tossed 562/3 shutout innings at Coors Field in the Sox' clinching World Series win last October. Lester may yet eclipse Matsuzaka as the team's No. 2 starter, but his postseason resume is, for now, lacking.

In contrast to recent seasons, there would appear to be opportunities for the Sox to deal for established starters before next month's trade deadline. Indications are that C.C. Sabathia, Erik Bedard, Rich Harden and A.J. Burnett all will be made available before July 31.

Most of those starters would be strictly short-term rentals for interested teams. Sabathia is eligible for free agency after this season and Burnett has an out-clause - similar to the one exercised by Red Sox outfielder J.D. Drew after 2006 - in his five-year, $55-million contract with Toronto that allows him to choose free agency.

Harden is eligible for free agency after this season, though his deal does include a $9-million club option for 2009. Finally, Bedard is under control through 2009.

In every case except Bedard's, the Sox could elect to be responsible for just two months' worth of salary and add two premium draft picks next June simply be offering arbitration to the rental pitcher on the way out the door.

Moreover, thanks to the progress shown by Masterson and the promise of Clay Buchholz, the Sox have an inventory of young arms from which they could deal. Michael Bowden, a sandwich pick from the 2005 draft, is dominating the Double-A Eastern League, and his inclusion in a package could land any of the aforementioned pitchers.

Surely, a rotation of Beckett, Sabathia, Lester and Colon would be the best of any team qualifying for the postseason.

But of the top four pitchers, how many can claim previous postseason success? Sabathia, perhaps weakened by his regular-season workload, was ineffective in two ALCS starts last year.

Harden, who made two postseason relief appearances against the Red Sox in 2003, has made just one postseason start. His checkered injury history, however, is enough to give pause to any team interested in being a trading partner.

Bedard and Burnett, meanwhile, have never appeared in the postseason.

In other words, Lester has as many postseason wins (one) as the four potential trade targets combined.

Of course, a lot can still happen between now and the start of the postseason. The Sox lead the American League in wins, but slightly more than half of the season remains. If anything were to happen to Beckett, or, say, Jonathan Papelbon, the Sox would be hard-pressed to make the postseason, much less advance deep into October.

But in a month's time, the Sox will be in a better position to assess what they have and what they need. And by then, it may be more important to find an upgrade for the bullpen than it is to augment an already deep - if somewhat inexperienced - starting rotation.