Arizona Diamondbacks vs Colorado Rockies Prediction – 6/21/2025

As the Colorado Rockies prepare to host the Arizona Diamondbacks on June 21, 2025, the stakes are high, especially after the D-Backs claimed a decisive 14-8 victory over the Rockies just yesterday. With the Rockies struggling at a dismal 17-59, they are far from contention, while the Diamondbacks sit at a more respectable 38-37, indicating a middle-of-the-pack season.

The matchup features two pitchers in contrasting forms. Carson Palmquist, projected to start for the Rockies, has had a rough year, posting an 0-4 record with a troubling 7.76 ERA. His last outing on June 16 saw him surrender 4 earned runs over 5 innings, a reflection of his season-long struggles. In contrast, Merrill Kelly of the Diamondbacks has been a bright spot, with a 6-3 record and a solid 3.41 ERA. Kelly's ability to limit walks (6.3 BB%) could be key against a Rockies offense that ranks 29th in the league in walks drawn.

Offensively, the Diamondbacks boast the 3rd best lineup in MLB, highlighted by their power with 108 home runs this season, while the Rockies' offense ranks a lowly 26th. The projections suggest that the Diamondbacks could score around 7.25 runs, compared to the Rockies' high implied total of 5.25 runs.

With a game total set at a lofty 12.5 runs, bettors should watch how Palmquist's flyball tendencies play against the D-Backs' powerful bats. Given the current trends and performance metrics, this matchup heavily favors Arizona, making them the likely choice for those looking to place bets.

Quick Takes Arizona Diamondbacks:

Merrill Kelly's cut-fastball percentage has fallen by 6% from last year to this one (25.2% to 19.2%) .

• Because cutters are one of the most effective pitches to use, a pitcher who alters his pitch mix to use them less often may see less success as a result, particularly if he uses his fastball more instead.

Ketel Marte has struggled with his Barrel% lately; his 13.7% seasonal rate has decreased to 0% in the last 7 days.

• Barrel% measures how often a player hits the ball at the optimal exit velocity and launch angle and is a terrific measure of underlying power.

According to the leading projection system (THE BAT), the Arizona Diamondbacks' bullpen profiles as the 9th-worst among all the teams in the league.

• Most bettors only consider the starting pitcher, but a weak bullpen sneakily creates an easier matchup for the opposing offense and boosts a game's runs.

Quick Takes Colorado Rockies:

In his last GS, Carson Palmquist didn't have his best stuff when it came to striking batters out and was only able to post 0 Ks.

• A pitcher who struggled in his last outing may have something wrong that affects him in his next outing as well.

Ryan McMahon has seen a significant improvement in his exit velocity this season; just compare his 94.5-mph average to last year's 92-mph average.

• Hitting the ball hard increases the chances of either a home run or the ball landing in fair territory for a hit before a fielder can get to it.

When estimating his overall offensive skill, Orlando Arcia ranks in the 15th percentile according to the leading projections (THE BAT X).

• THE BAT X is a highly sophisticated projection system that accounts for a multitude of factors and regularly tests among the most accurate systems available.

Game Trends

• The Colorado Rockies have hit the 1st Five Innings (F5) Team Total Under in 46 of their last 75 games (+12.65 Units / 13% ROI)
• The Arizona Diamondbacks have hit the 1st Five Innings (F5) Moneyline in 25 of their last 42 games (+13.50 Units / 22% ROI)
• Hunter Goodman has hit the Total Bases Over in 11 of his last 15 games (+7.75 Units / 48% ROI)

Arizona Diamondbacks vs Colorado Rockies Prediction

Predicted Final Score: Arizona Diamondbacks 7.18, Colorado Rockies 5.97

• Date: June 21, 2025
• Venue: Coors Field
• Starting Pitchers:
  • Merrill Kelly - D-Backs
  • Carson Palmquist - Rockies

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