The Colorado Rockies are in such a funk, not even a visit from one of the worst teams in the majors can snap them out of it. Colorado has lost five straight and nine of its last 11 games to plummet out of contention in the National League West as it hosts the Arizona Diamondbacks on Wednesday in the middle contest of a three-game series. The Rockies began a 10-game homestand with a 4-2 loss Tuesday as Jorge De La Rosa fell to 38-13 at Coors Field with his first loss in seven decisions and could lose Carlos Gonzalez to the disabled list after their star left fielder departed Tuesday's contest after inflammation reoccurred in his left index finger."I really don't know what to do now at this point," Gonzalez, who also has a sore knee, told reporters about his finger. "It's frustrating. This is the third time." Arizona is 19-18 in its last 37 games after starting 5-18 and will be even tougher to beat with a refreshed Paul Goldschmidt back in the lineup after the first baseman, who played the first 59 games, was given Tuesday off. The Diamondbacks' Josh Collmenter is coming off his first career complete game - a shutout in which he faced the minimum 27 batters - while winning his fourth straight decision and opposes Jordan Lyles, who is winless in his last three turns.TV: 8:40 p.m. ET, FSN Arizona, ROOT (Colorado)PITCHING MATCHUP: Diamondbacks RH Josh Collmenter (4-2, 3.34 ERA) vs. Rockies RH Jordan Lyles (5-1, 3.46)Collmenter joined Randy Johnson (perfect game in 2004) as the only Arizona pitchers to face the minimum when he pitched a three-hitter and benefited from three double plays in a 4-0 victory over Cincinnati on Friday. ''He was just kind of in the zone, throwing his pitches right where he wanted them,'' Arizona manager Kirk Gibson told reporters about the 28-year-old Michigan native while Reds manager Bryan Price added: ''We didn't barrel many balls.'' Collmenter is 2-1 with a 4.10 ERA in 16 games (six starts) versus Colorado while taming Troy Tulowitzki (3-for-14), but having trouble with Gonzalez (5-for-12, two homers, three RBIs).Lyles was 5-0 with a 2.66 ERA after winning at Cincinnati on May 10, but 0-1, 6.28 in three starts since after yielding two runs, five hits and four walks in five innings and earning a no-decision in Colorado's 6-3 loss at Philadelphia on Wednesday. The 23-year-old South Carolina native has yielded more than three runs in only two of his 11 starts this season. Lyles is 0-2 with a 7.82 ERA in four career starts against the Diamondbacks - including a no-decision in a 5-4 loss at Arizona on April 30 when he yielded one run in six innings - while struggling with Miguel Montero and Gerardo Parra (combined 10-for-21, four doubles).WALK-OFFS1. Arizona on Tuesday placed INF Cliff Pennington on the 15-day disabled list - retroactive to Monday - with a sprained ligament in his left thumb and recalled INF Didi Gregorius from Triple-A Reno. Gregorius hit .310 with 25 RBIs and 42 runs scored - second in the Pacific Coast League - in 57 games with the Aces.2. Diamondbacks SS Chris Owings homered among his three hits Tuesday and was a single shy of hitting for the cycle.3. Nick Evans on Tuesday filled in at first base for Arizona and hit his first home run since 2011 while a member of the New York Mets.PREDICTION: Rockies 6, Diamondbacks 5