Jimenez, 26, became the Rockies' top pitcher last season, when he went 15-12 with a club-record 3.47 ERA. From May 1 to Sept. 7, he went six or more innings in 25 consecutive starts. It was just a matter of time before Tracy would tap Jimenez for April 5 against the Brewers at Miller Park.
Veteran righty Aaron Cook started Rockies openers in 2007 and '09 -- years that finished with the Rockies in the playoffs. Cook had a nice year last year, too -- 11-6 with a 4.16 ERA. But he knew Jimenez deserved the nod this year, and wanted to stamp his approval on the decision.
"About 12 days ago or so, Aaron Cook came to me and said, 'Trace, I think I have a pretty good idea the direction you're going in, and when you get to the point to where you're ready to make the announcement, I'd like to be in there with you to congratulate him,'" Tracy said.
"That's exactly what took place. So the meeting that took place was between myself, Ubaldo Jimenez and Aaron Cook, who very unselfishly is handing the torch to him."
Jimenez said it's more like he has a share of the torch, not the whole flame.
"I have a lot of respect for him [Cook], but right now, I have even more respect for what he did," said Jimenez, who will likely be facing the Brewers' Yovani Gallardo in the opener. "After Tracy told me, we walked outside and he gave me a lot of advice about Opening Day. He told me to take it just as another game, be prepared for it and just enjoy it."
Cook said he never experienced jealousy from other pitchers on the occasions the Rockies named him to start the opener. But during his drive to Tucson, he decided he wanted to leave no doubt that he was happy for Jimenez.
"That's what's special about this game," Cook said. "When people go through their careers and realize things start to change, pass the torch to somebody else, let them carry it for awhile.
"I didn't do it for me. I didn't do it for anybody else, just for him, just so he knows. Opening Day is tough enough. I don't want him looking over his shoulder. I don't think he would. He knows I don't feel that way. But for me it was, put it out in the open. 'Go get 'em. You're the guy.'"
Jimenez has pitched in the postseason. He started Game 1 of last year's National League Division Series. But Cook can offer perspective on pitching amid the ceremony of the opener.
"I said the biggest thing is trying to figure out when you're supposed to get loose for the game, with all the introductions and flags on the field and people running around," Cook said. "Then you're trying not to hit somebody. I came close to hitting a couple of military guys. I felt pretty bad about it. I was trying to get loose for the game and let one fly."
Tracy considered informing Jimenez after his first spring appearance. But the first scheduled start became a relief appearance against the Angels when Jimenez -- trying to drive to Tempe, Ariz., to meet the team -- was stuck in a traffic snarl that resulted from a tragic auto accident on I-10.
But Jimenez's second appearance, against the Dodgers on Tuesday, so impressed Tracy that he could not hold back any longer. Jimenez threw three scoreless innings in Colorado's 12-0 victory, but Tracy was more impressed with how Jimenez attacked hitters.
The Rockies have insisted pitchers rely on their fastball, force hitters to put the ball into play and let an outstanding defense do its work. Jimenez struck out 198 in 218 innings last year. Tracy believes Jimenez can increase his innings by being more efficient with his pitches. He saw that efficiency on Tuesday.
"I saw him throw a number of fastballs yesterday in counts where there could've been another choice," Tracy said. "But it was obvious he was using his day's work on establishing his fastball, the capability of being able to throw it wherever he wants and whenever he wants."
Jimenez said any of the pitchers deserved to be honored. Jorge De La Rosa led the staff with 16 wins, Jason Hammel won 10 in his first season as a starter, and Jeff Francis, bothered by injuries the past two years, was the Opening Day starter in 2008.
"I feel like another ace on our team, because we have four more aces," Jimenez said.
Thomas Harding is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.