The Marlins (74-82) will be trying to clinch the three-game series after their 5-4 victory Monday.
Miami manager Don Mattingly said the club was fortunate Urena has emerged, considering only Dan Straily and Adam Conley are left from an Opening Day rotation that already lacked Jose Fernandez, who was killed in a boating accident exactly one year ago Monday.
When it was suggested that Urena (14-6, 3.55 ERA) has been a godsend, Mattingly quickly agreed. The Marlins are 17-9 in games started by the right-hander, who will be opposed Tuesday by Rockies left-hander Tyler Anderson (5-6, 5.24 ERA).
Urena, 26, began the season with seven relief appearances before joining the rotation May 7. He is 5-5 with a 3.08 ERA in 16 games (13 starts) in Miami, 9-1 with a 4.08 ERA in 16 games (13 starts) in outings elsewhere.
"I think he's become less of a thrower," Mattingly said. "He's pitched more. He's always been a guy with a power arm, power stuff. Was still getting to the next level of basically being able to try to get the ball to both sides of the plate, use his breaking ball more often, use his off-speed (stuff), not just trying to overpower guys."
Urena's changeup is his best secondary pitch. His slider has improved, and he can sit at 96-97 mph with his fastball. Mattingly said Urena works hard and has a desire to be great.
"He keeps you in every game, pretty much," Mattingly said. "But sometimes it was 100 pitches in five innings, and we were trying to push him to: 'Hey, you don't have to try and strike everybody out. You can let them put the ball in play. Just make quality pitches, you're going to get outs.'"
In four starts this month, Urena is 2-0 with a 2.08 ERA. While winning his latest start, Wednesday against the New York Mets, Urena allowed two runs in a season-high-tying eight innings, throwing a season-high 107 pitches in Miami's 9-2 victory.
He is 1-0 with a 2.50 ERA in three career starts against the Rockies, including a no-decision Aug. 11 at Miami when he allowed six hits and three runs in 5 1/3 innings and left trailing 3-1 before the Marlins won 6-3. Urena is 0-0 with a 1.50 ERA in one start at Coors Field. He allowed one run and three hits in six innings on June 7, 2015.
"Guys like playing behind him," Mattingly said. "He works fairly quick. We know he's going to be aggressive. He's not afraid. He's going to attack, no matter who it is and who we're playing."
Anderson, who is 0-1 with a 3.18 ERA in one career start against the Marlins last year, has given the Rockies' staff a late-season lift. In three games, including two starts, since being reinstated Sept. 10 following left knee surgery in July, Anderson is 2-1 with a 1.72 ERA. In that span, he allowed nine hits, three runs and three walks in 15 2/3 innings with 13 strikeouts while limiting opposing hitters to a .173 batting average.
"He's come back with a renewed vigor to contribute," Rockies manager Bud Black said. "I think that's the main thing. He's pitching with a high degree of focus, and physically he's fresh. Velocity's returned, and that's a function of just repetition and being out there.
"He's built to throw strikes. His intent is to throw strikes. He doesn't work around the zone even though his strength is hitting the glove and hitting spots. He's doing really well, very pleased with where he is."