MLB Odds, Picks and Predictions: Colorado Rockies vs. Arizona Diamondbacks (Monday, August 24)

Colorado Rockies vs. Arizona Diamondbacks Betting Odds

Odds as of Monday at 9:30 a.m. ET and via DraftKings. Get up to a $1,000 sign-up bonus at DraftKings today or see more offers and reviews for the best online sportsbooks.

The Colorado Rockies and Arizona Diamondbacks are both in desperate need of a win. The Rockies are winless in their last seven after playing a home-and-home series with the Astros followed by a three-game road series against the Dodgers. They’ll travel to Arizona where they’ll face a Diamondbacks team that returns home off a disappointing five-game road trip where they failed win a game and averaged just 1.25 runs per game.

Last week in one of my pieces, I discussed Arizona’s struggles on the road, particularly in ballparks that aren’t so hitter-friendly. While they return home to the friendlier confines of Chase Field, I’m not ready to pencil them in for a victory just yet. I think the bookmakers are looking to exploit a bias that bettors might have with Arizona at home.

In turn, that might create just enough value to make the other side more attractive in this matchup.

Arizona Diamondbacks

Arizona will send Merrill Kelly to the mound to try to put an end to its five-game skid. Kelly is off to a good start this season with a 3-2 record and 2.59 ERA. Some caution is warranted, however, as his 3.94 FIP, which is higher than his ERA, suggests that he could be due for some regression in the near future.

That regression could come at the hands of tonight’s opponent, the Colorado Rockies. The Rockies are 2-1 against the Diamondbacks with Kelly on the mound and their hitters have enjoyed success against the Arizona right-hander.

In 51 at-bats, the Rockies are hitting .353 with three home runs and 12 RBIs. Their weighted on-base percentage (wOBA) against him is .446 with an OPS of 1.044. This season, Colorado is ranked just one below the Diamondbacks with a wRC+ value of 84. This suggests to me that both offenses are just about even coming into this matchup.

Colorado Rockies

Kelly will be opposed by rookie right-hander, Ryan Castellani, who will be making his fourth big-league start.

This start figures to be a sentimental one for Castellani who grew up in Phoenix and likely sat in the stands watching the Diamondbacks as a youngster.

Castellani is 0-1 with a 3.77 ERA and 0.98 WHIP. Similar to Kelly, his 5.37 FIP is higher than his ERA which could lead to some regression in upcoming games. Though it may take some time as hitters are just seeing Castellani for the first time given that it's his first year in the majors.

Despite picking up the loss in his last start, Castellani made some progress by pitching into the sixth inning for the first time in his career. Tonight’s start presents an opportunity for him to take another step forward to picking up his first win.

Betting Analysis

Using the Bill James Pythagorean Expectation, we can estimate the percentage of games that both the Rockies and Diamondbacks should have won at this juncture. At 13-15 the Rockies have a .464 winning percentage yet they have an expected win percentage of .497, while the Diamondbacks at 13-16 have a .448 winning percentage with an expected win percentage of .420. The answer to this debate of who is the better team is probably closer to the middle than anywhere else on the spectrum. That’s why I’m cautious to lay 1.5-to-1 to back Arizona as the favorite in this matchup.

DraftKings is listing the Diamondbacks current odds at -167 which is an implied probability of 62.6%.

I just don’t see these two teams that far apart especially when you consider that the Rockies have a +23 edge head-to-head in run differential.

This will be the Diamondbacks' first time taking live at-bats against Castellani which could work to the pitcher’s advantage. While on the other side Kelly will have to deal with a Rockies lineup that should fancy their chances against him given their .353 / .377 / .667 slash rate.

BetMGM has the underdog Rockies at +145 which seems a bit generous given the points I’ve already laid out. I’m not one to pass up on value so I’ll take Colorado and hope that there’s just a little bit more motivation on their side with Castellani pitching in his home state.

The PICK: Rockies moneyline +145 (play down to +135) [Bet now at BetMGM and get a $500 INSTANT deposit match]