From Brian Costa:

The Yankees won’t have to face Cliff Lee again until Game 5 of the World Series. The Phillies named Joe Blanton their Game 4 starter Friday, opting to use a fourth starter rather than bring Lee back on short rest.
Phillies manager Charlie Manuel said he was reluctant to have Lee pitch on just three days’ rest because he has never done it before in the majors.
“I don’t think he’s ready to go on three days’ rest,” Manuel said before the Phillies worked out at Citizens Bank Park. “That would be really pushing it, because he’s never done it before.”
Blanton, a right-hander, was 12-8 with a 4.05 ERA during the regular season. He has a 4.50 ERA in three appearances (one start) this postseason.

Blanton is not a terrible starter at all, and has some experience with American league lineups. He has terrible career numbers against the Yankees (8.18 ERA), but those represent a very small sample and are skewed by one awful start. That being said, I think Manuel is making a mistake here. Not only does this give the Yankees a major advantage in Game 4, it gives them the upper hand for a possible game 7. Game 5 would be Lee’s last start of the series, meaning the Yankees would get to face Pedro Martinez and Cole Hamels at home. While neither of those pitchers are slouches, they are most certainly not Cliff Lee. This is how it is likely to play out, assuming the Yankees use only three starters, courtesy of Rob Neyer:

Game 3: Pettitte vs. Hamels (advantage: Yankees)
Game 4: Sabathia vs. Blanton (Yankees)
Game 5: Burnett vs. Lee (Phillies)
Game 6: Pettitte vs. Martinez or Happ (Yankees)
Game 7: Sabathia vs. Hamels (Yankees)

If the Yankees happen to take Games 3 and 4, you might see Chad Gaudin in Game 5, with Game 6 going to Burnett and Game 7 to Sabathia, with Pettitte available in relief for both of those games.

I understand that Manuel is worried about wasting his greatest asset by using him in a manner that may sap his effectiveness. However, he is creating a situation where the Yankees can lose to Lee and even once to Hamels and still win the series. He would be better served by using Lee in Games 4 and 7, and pitching Blanton in Game 5 and Hamels/Martinez in Game 6. The Yankees just caught a break.