Farrell said after Boston's 8-1 victory in Game 1 on Wednesday night that he will likely give Buchholz another day of rest.
"We'll probably look to give him every extra day we can," Farrell said, "and that would point to Sunday, being Game 4."
Buchholz gave up five runs in eight innings and two runs in five innings in his AL championship series starts against Detroit; Peavy gave up seven runs in three innings in his only ALCS start. Asked before the World Series opener whether Buchholz had an injury, Farrell said, "Not to the point of keeping him out of starting."
Farrell said he wanted to see the Cardinals in the first two games; his decision also could be influenced by whether it looks as if the Red Sox would need their Game 3 starter to come back for a potential seventh game.
Jon Lester started against St. Louis' Adam Wainwright in Game 1, with John Lackey scheduled to go for Boston against Michael Wacha in Game 2 on Thursday night at Fenway Park. St. Louis is expected to start Joe Kelly and Lance Lynn in Games 3 and 4.
Wacha, a rookie whom the Cardinals obtained with a compensatory draft pick when Albert Pujols signed with the Angels, was 4-1 with a 2.78 ERA in the regular season, spending part of the year with Triple-A Memphis. He is 3-0 with a 0.43 ERA in the post-season.
"I want the ball in big situations. There's none bigger than the World Series," Wacha said. "And so I'm excited about getting it and I think every guy on our team wants the ball in these kinds of situations."
When he found out he would be starting Game 2 at Fenway Park — his first time pitching in the ballpark — it created a whole bunch of new things to be excited — and worried — about.
"This is kind of a tricky little ballpark with the dimensions and that kind of stuff. One pitch can really kind of change a game," Wacha said. "You try not to think too much about it, just try to approach it just like any other game, any other stadium. And that's just making pitches down in the zone and try not to give them too much of a chance to lift it."