Left-hander Jeff Francis, who took over leadership of the staff in Cook's absence and has won 19 games (including both postseason starts), is set for Game 1. Rookie right-hander Ubaldo Jimenez, who has a 1.59 ERA in two postseason starts, is set for Game 2.
The Rockies haven't announced anything beyond that. But Cook and Josh Fogg, who has a win in relief and one as a starter in the postseason, were the starting pitchers for Saturday's intrasquad game.
Cook pitched 4 2/3 innings and gave up three earned runs, including a homer, and four hits. He struck out three and walked two.
Rookie left-hander Franklin Morales, who has had starts of just three and four innings in the postseason, entered the game toward the end of Saturday's workout after a lengthy bullpen session.
Before the workout, Morales felt ill and, while holding his medication bottle, politely declined an interview request. But Morales threw two scoreless innings, with two walks.
Originally, Cook expected to throw Sunday. The Rockies are still scheduled to work out on Sunday, but a snow/rain mix is expected in the Denver area.
The Rockies haven't announced any roster decisions and have until Wednesday, the morning of Game 1 on the road against either the Indians or the Red Sox.
Cook had thrown one rehab game in Arizona instructional ball before the National League Championship Series and felt ready, but manager Clint Hurdle determined that wasn't enough and didn't activate him. Since then, Cook has thrown a simulated game and Saturday's intrasquad game.
Cook, who overcame a slow start and was 8-7 with a 4.12 ERA during the regular season, rejected the notion that he was auditioning on Saturday.
"I was the Opening Day starter," Cook said. "I've been in this organization 12 years. I think they know what they can count on."
The Rockies are scheduled to head to the American League champion's city after Monday's workout and will have a session in that city Tuesday.
Intrasquad World Series moment No. 1: Second baseman Kazuo Matsui pulled a Cook pitch to deep right-center field. It bounced off the top of the wall and into the bullpen for a two-run homer.
As Matsui headed toward second, he raised his right fist, drawing laughter from his teammates.
Cook strode to home plate and waited for Matsui. Was he upset at the gesture?
Nah. Cook smiled and bumped fists with Matsui.
Intrasquad World Series moment No. 2: Because the intrasquad game was based more on the pitchers than actual baseball, Cook's inning ended after Matsui's home run, and Fogg pitched.
Infielder Omar Quintanilla, who has not been active for either playoff round and who has never hit a Major League home run, blasted one over the center-field wall. Quintanilla also gave the obligatory skyward point.
For what it's worth: After batting .154 (4-for-26) in the postseason, first baseman Todd Helton welcomed the eight-day break between the NLCS and the World Series to recharge himself. If the intrasquad game is an indication, the plan may be working. He went 5-for-6 with two doubles and two RBIs.
Fogg went five innings and gave up two runs, including the Quintanilla homer, and five hits, with three strikeouts and a walk.
Their World Series thrill: Former Minor League umpire Jeremy Sparling invited his friend, Randy Jones, another former Minor League ump, to visit the Denver area from Norfolk, Va.
Little did they know they'd receive a taste of the World Series.
The Rockies needed umpires to give pitchers and hitters a realistic feel for pitches and plays on the bases. So the Rockies called Sparling, 30, and he had a ready partner in Jones, 45, who is considering moving to the Denver area.
"We had done some local men's league stuff last weekend, so it was one of those things," said Sparling, still shocked to go from men's league to big league.
Roger Wolfe, who fills in for vacationing umpires in the Eastern League and South Atlantic League, worked at Coors Field on Friday.
Sparling umpired for five years, through the Double-A Texas League, before leaving to spend time with family. Jones, who worked in the Class A South Atlantic League, now calls Division I collegiate games in the Mid-Eastern Athletic Conference and the Colonial Athletic Association.
This is special for Jones, who refused to cross the picket line during a Minor League umpire strike a few years back but wound up losing his footing in pro ball.
"I called my wife last night and said, 'I hadn't done anything since I didn't cross. I stayed true to my brothers,'" Jones said.
There were no fans in the stands, but don't tell these guys it wasn't a big-time atmosphere.
"When we got done yesterday, [Rockies GM] Dan O'Dowd, Clint Hurdle, everybody was just, 'Thank you so much for coming,'" said Sparling, who brought his wife and 10-year-old son to Coors to see the Rockies clinch the NLCS. "I'm thinking, 'Thank you.' This is such a thrill for us.
"Hopefully, we'll get to work tomorrow. If not, it's two days more than I've ever worked in a big league stadium with a big league club getting ready for the World Series."