Arizona Diamondbacks vs Colorado Rockies Picks and Prediction for Wednesday September 23 2026

The Arizona Diamondbacks visit the Colorado Rockies at Coors Field in Denver, Colorado, on Wednesday, September 23, 2026. First pitch is scheduled for 8:40 PM ET with coverage on MLB.TV. Arizona enters at 82-74 overall and 37-38 on the road, while Colorado is 57-99 overall and 32-46 at home. The Diamondbacks sit third in the NL West and entered this series on a two-game winning streak, while Colorado is last in the division and had dropped four of its previous five completed games. Arizona leads the completed season series 6-4 entering the current set at Coors Field. Tuesday's series opener had not been completed in the supplied information and is not included in the recent-form analysis. At the time of this writing the odds were not released. Be sure to check out our free MLB picks for more MLB predictions throughout the season.

Starting Pitchers

Arizona is scheduled to start Merrill Kelly, who enters at 9-14 with a 5.00 ERA and 1.47 WHIP through 156.2 innings. He has allowed 162 hits and 28 home runs while striking out 111 and walking 69. Colorado counters with Mason Adams, who is 0-1 with a 5.09 ERA and 1.65 WHIP through 23 innings. He has surrendered 26 hits and six home runs while recording 23 strikeouts against 12 walks. Neither starter brings dominant season numbers into this matchup, and both have allowed more than one baserunner per inning at a significant rate. Kelly has considerably more major-league workload behind his numbers, while Adams enters with a limited 23-inning sample. With both ERAs sitting at 5.00 or higher, the starting matchup provides reasons to expect scoring opportunities on both sides.

Arizona Tries to Build on Consecutive Wins

Arizona enters Wednesday at 82-74 overall and sits third in the NL West, 14 games behind Los Angeles and five games behind San Diego in the supplied standings. The Diamondbacks are 37-38 away from home and went 2-3 over their five most recently completed games. Both victories came in their last two contests, beating New York 5-3 and 8-4. Before those wins, Arizona lost three straight by scores of 9-2, 4-3 and 4-2. The Diamondbacks scored 20 runs and allowed 24 during that five-game stretch, but 13 of those runs came in their two most recent victories.

Arizona is batting .244 with 693 runs, 1,276 hits and 157 home runs. The Diamondbacks carry a .316 on-base percentage and .398 slugging percentage. Their pitching staff has posted a 4.11 ERA and 1.28 WHIP while allowing opponents to bat .248. Arizona pitchers have issued 467 walks and recorded 1,094 strikeouts. Those numbers are not overwhelming, but almost every major pitching category gives the Diamondbacks a considerable advantage over Colorado.

The clearest strength for Arizona in this matchup is the gap between the two pitching staffs. Arizona's 4.11 team ERA is 1.46 runs better than Colorado's 5.57 mark, while its 1.28 WHIP is substantially lower than the Rockies' 1.53. The Diamondbacks have also limited opponents to a .248 batting average compared with Colorado allowing a .288 mark. Arizona's offense does not have to dominate for the Diamondbacks to have an advantage if the pitching disparity carries into Wednesday night.

Colorado's Offense Has to Carry the Load

Colorado enters at 57-99 overall and is last in the NL West, 39 games behind Los Angeles in the supplied standings. The Rockies are 32-46 at Coors Field and have lost four of their five most recently completed games. Colorado's lone victory during that stretch was a 5-3 win over Seattle. The losses came by scores of 2-1, 5-4, 9-2 and 9-3. The Rockies scored 15 runs and surrendered 28 over those five games, with their opponents averaging 5.6 runs per contest.

The Rockies are batting .254 with 727 runs, 1,351 hits and 170 home runs. Colorado owns a .323 on-base percentage and .416 slugging percentage, giving the Rockies an advantage over Arizona in each of those offensive categories. Pitching has been an entirely different story. Colorado owns a 5.57 team ERA and 1.53 WHIP while opponents are batting .288. The staff has issued 519 walks and recorded 1,072 strikeouts.

Colorado's offensive numbers make the Rockies dangerous enough to prevent this matchup from being an automatic Arizona selection, especially at Coors Field. They have scored 34 more runs than the Diamondbacks while producing better marks in batting average, on-base percentage and slugging percentage. The problem is overcoming a pitching staff that has allowed opponents to hit .288 and routinely puts additional runners on base. Colorado's starter also enters with a 5.09 ERA and 1.65 WHIP, so the Rockies may need their offense to produce significant run support to keep pace.

Arizona Diamondbacks vs Colorado Rockies Picks and Prediction

Pick: Arizona Diamondbacks Moneyline

Arizona gets the side selection because the difference between these pitching staffs is too substantial to overlook. The Diamondbacks have a 4.11 team ERA, 1.28 WHIP and .248 opponent batting average compared with Colorado's 5.57 ERA, 1.53 WHIP and .288 opponent batting average. Colorado owns the better offensive statistics, but Arizona has the stronger overall record, enters on consecutive wins and has already taken six of the first 10 completed meetings this season. The starting matchup is not overwhelmingly favorable to Arizona, but the Diamondbacks have the more reliable overall pitching profile behind their starter. With no confirmed line supplied, the moneyline is preferable to projecting an Arizona run-line price.

Pick: Over 9.5 or Lower

This is a matchup where the over deserves serious consideration if the total opens at 9.5 or lower. Both scheduled starters carry ERAs of at least 5.00, while Colorado's staff owns a 5.57 ERA and has allowed opponents to hit .288. Arizona has scored 13 runs over its last two completed games, and Colorado has produced the better full-season offensive numbers with a .254 average, .323 OBP and .416 slugging percentage. The Rockies' offense gives them a reasonable chance to contribute against an Arizona starter with a 5.00 ERA and 1.47 WHIP, while the Colorado pitching numbers create significant scoring potential for the Diamondbacks. The combination of vulnerable starting pitching and Colorado's season-long run-prevention problems makes the over the preferred total at 9.5 or lower.

Final Picks: Arizona Diamondbacks Moneyline and Over 9.5 or Lower

This preview was completed on Tuesday, September 22, 2026. Starting pitchers, betting lines and other game information are subject to change before the game begins.