"Iannetta made me decide, 'Throw hard ... throw with everything you have,'" Jimenez said. "That's what I did."
Jimenez's 3-1 pitch was a 95-mph fastball. He took a deep breath as Montero, whom he recalled hit an opposite-field home run off him on Aug. 31, 2007, that cost Jimenez a win (the Rockies won in 10 innings), swung with every ounce of energy. Jimenez answered with a 97-mph inside fastball that Montero had no prayer of hitting.
Although it was just the second game of the season, the Rockies badly needed Jimenez's display of trickery and brawn as he held the D-backs to four hits and three walks.
Jimenez displayed old-time diversity, in an age where hurlers rarely use more than three different pitches. Part of it, he said, was pitching in a climate that was perfect for his repertoire. He has pitched well in the altitude at Coors Field, even though sometimes certain pitches like the curve don't work.
Even more, it came when the Rockies needed it most.
Monday afternoon's opener was wild. The starting pitchers were sinkerballers -- the Rockies' Aaron Cook against the D-backs' Brandon Webb -- yet balls flew. The game included eight home runs, with the D-backs knocking five and winning, 9-8. One game, sure, but counting last year, it was the Rockies' 16th loss to Arizona in 19 games since Colorado swept the 2007 National League Championship Series.
Also, after Cook lasted just 2 1/3 in the opener, the bullpen would have had difficulty absorbing another bad start.
"The timing of it might not have been ever better," Rockies manager Clint Hurdle said.
Jimenez managed to overshadow D-backs starter Dan Haren (0-1), who actually had a slightly better line in terms of strikeouts (nine) and hits (three). However, one hit was Rockies shortstop Troy Tulowitzki's leadoff home run in the fifth, his second solo shot in as many games.
"I threw quite a few breaking balls throughout the game and he was sitting on it," Haren said. "Maybe I made the adjustment one pitch too late, but it wasn't like it was a hanger."
Jimenez made the right pitches on the two occasions that he faced trouble. He used his fastball to work Haren into a double-play grounder with one out and the bases loaded in the second.
The challenges he won against Montero came after Stephen Drew doubled off the top of the right-field fence with one down and Conor Jackson drew a walk with two out.
Jimenez finished with his strongest inning -- strikeouts of Mark Reynolds and Justin Upton, and snapped pinch-hitter Eric Byrnes' bat for a groundball.
Jimenez, 25, went 12-12 with a 3.99 ERA last season, his first full year in the Majors. He went 8-3 with a 3.68 ERA after the break.
This spring, he had two dominating performances with the Dominican Republic's World Baseball Classic team, a short but impressive game against the Cardinals and a Classic-record 10 strikeouts in four innings against The Netherlands. That also might have prepared him for a tense game this early.
"Tonight, before every pitch, I was able to think about what I wanted to do," Jimenez said. "Before, it was like whatever the catcher put down, I'd throw it. Tonight, I was able to think with Iannetta."
Pinch-hitter Ian Stewart and Todd Helton added RBI singles in the eighth.
The final two innings were almost as much a boon for the Rockies as Jimenez's time on the mound. Manuel Corpas struck out one in a spotless eighth. Huston Street, one of three players the Rockies received for former star left fielder Matt Holliday, gave up one hit and struck out one in the ninth for his first save with Colorado.