PHOENIX — Miguel Montero hit a leadoff homer in the 10th inning after Martin Prado hit a two-run single in the ninth, helping the Arizona Diamondbacks end a four-game losing streak with a 5-4 win over the Colorado Rockies Wednesday night.
Colorado led 4-0 after three innings behind Carlos Gonzalez's two-run homer and pitcher Jordan Lyles' leadoff shot in the third.
The Rockies' bats went quiet after that and Arizona cut into the lead on Paul Goldschmidt's solo homer in the eighth inning. The Diamondbacks then loaded the bases with two outs in the ninth against Rex Brothers, and Prado tied it at 4 with a two-run single up the middle.
Addison Reed (1-2) stranded a runner at third in the 10th inning and Montero ended it with his first career walkoff hit, a towering homer to right off Tommy Kahnle (2-1)
Nolan Arenado extended his majors-best hitting streak to 20 games with a single in the sixth inning for the Rockies, who had three hits after the third inning.
The Rockies beat up on Arizona's pitching the first two games of the series, with 13 runs and 23 hits, including 12 for extra bases.
They kept it up early against Josh Collmenter — with a little help from the right-hander.
Gonzalez got it going in the first inning, eking a two-run homer just over the wall in the right.
Collmenter had a wild pitch to advance Jordan Pacheco to third in the second inning, but got a break when he was called out on appeal for leaving the base too early on a fly to right.
Lyles led off the third with his first homer on Sept. 30, 2012, with the Astros at Milwaukee, and Collmenter followed with another wild pitch that scored Charlie Blackmon to put Colorado up 4-0.
Collmenter settled in after that, retiring 10 straight batters until Arenado's two-out single in the sixth inning.
Collmenter allowed four runs on seven hits in seven innings.
That kept the Diamondbacks in it, but they couldn't get much going against Lyles.
Prado hit a one-out triple off Lyles in the first inning, but was thrown out at the plate trying to score on a grounder by Goldschmidt.
Arizona loaded the bases against Lyles in the sixth, scoring just one run, on Aaron Hill's groundout. The Diamondbacks struggled in a similar situation the night before, failing to score with the bases loaded and no outs in a 5-4 loss to the Rockies.
Lyles allowed a run on three hits in six innings.
Goldschmidt hit his homer off Adam Ottavino in the eighth inning, trimming the lead to 4-2, setting up the dramatic finish the Diamondbacks desperately needed.
NOTES: Arizona's starters have allowed 28 homers, most in the majors. ... Colorado's Justin Morneau went 0 for 4 to end a 13-game hitting streak. ... The Diamondbacks have Thursday off before starting a three-game road series against San Diego with RHP Bronson Arroyo on the mound. ... RHP Juan Nicasio pitches for Colorado against the New York Mets on Thursday to start a six-game homestand.