Both teams probably like their chances with the starters they'll have in the game.
Scherzer, who was 16-7 in the regular season with 231 strikeouts that trailed only teammate Justin Verlander's baseball-leading total, is 0-1 with an 0.82 ERA this postseason.
He was on pace for a victory in Game 4 of the AL division series against the Oakland Athletics until Jose Valverde blew the lead in the ninth inning. Scherzer allowed one run in 5 2-3 innings of Detroit's AL pennant-clinching win over the New York Yankees.
By starting on Sunday, Scherzer will have pitched Game 4 of all three postseason series.
Cain, meanwhile, hasn't been quite as sharp in the playoffs as he was during the regular season.
He is 2-2 with a 3.52 ERA in the postseason after throwing a perfect game in June and going 16-5 with a 2.79 ERA for the season.
Cain pitched 5 2-3 scoreless innings and drove in a run to help San Francisco beat St. Louis in Game 7 of the NLCS after giving up three runs in each of his first three postseason starts.
CROWNING ACHIEVEMENT: Bud Selig presented Miguel Cabrera with an actual crown Saturday, recognizing the Triple Crown he won this season, and announced that the Tigers slugger won the AL's Hank Aaron Award.
For the first time, both winners of the award that recognizes the top offensive players in each league were getting ready to play in the same World Series.
After Cabrera posed for pictures and made a statement, he went to get ready for Game 3. Moments later, Giants catcher Buster Posey was honored for being the NL's Hank Aaron Award winner.
"Miguel joined historic company this year by winning the game's first Triple Crown in 45 years," Selig said. "And, Buster was a consistent force in returning to the field triumphantly this year."
Cabrera is the first player to lead a league in batting average, home runs and RBIs since 1967 when Boston's Carl Yastrzemski pulled off the feat.
"I am very nervous right now," Cabrera said after waiting for more than 10 minutes for Selig to arrive at the pregame news conference. "But I want to thank you very much. It's an honor to be sitting here with a Hall of Famer and commissioner."
Posey hit .336 and became the first catcher in the league win the batting title since Ernie Lombardi of the Boston Braves in 1942.
"I'm humbled that Hank Aaron knows who I am," Posey said. "Growing up in Georgia, he's a legend."
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