Arizona Diamondbacks 2021 Season Preview, Odds & Outlook

Arizona Diamondbacks Logo With MLB Background

Like the San Francisco Giants and Colorado Rockies, the Arizona Diamondbacks could get lost in the NL West shuffle in a hurry.

The Dodgers upgraded once again by nabbing the top free-agent pitcher on the market in Trevor Bauer while the Padres made a litany of moves, most notably starting-pitching related, in an effort to overcome the reigning champs in 2021.

That said, you never say never, so let’s take a look at what transpired this offseason in Arizona while looking into their odds and outlook for the 2021 season!

*Odds courtesy of BetOnline

Arizona Diamondbacks 2021 Betting Odds

  • NL West (+4000)
  • NL Pennant (+6600)
  • 2021 World Series (+12500)

Arizona Diamondbacks 2021 Season Preview

Starting Pitching

  • Last season: 5.04 ERA (22nd) / 5.12 FIP (26th)
  • Key Offseason Additions: None

The D-backs traded Zack Greinke to the Houston Astros at the 2019 trade deadline and traded away Robbie Ray to the Blue Jays around the 2020 deadline, eliminating two pitchers who had spent years in that D-backs rotation.

The inaugural season in Arizona for Giants legends Madison Bumgarner was a disaster as the southpaw worked to a 6.48 ERA/7.19 FIP across nine starts.

The good news is a star emerged in the form of right-hander Zac Gallen who turned in a 2.75 ERA/3.66 FIP and a 10.25 K/9 while leading all D-backs starters with a 1.5 fWAR as part of his 12 starts and team-leading 72 innings.

The team will most certainly look for a bounce-back effort from Bumgarner, but it’s far from guaranteed with plenty of mileage on that left arm. Gallen is now the ace to be sure, but the team will also need the likes of Luke Weaver, Alex Young, Caleb Smith, Merrill Kelly and Corbin Martin to create a healthy internal competition in order to have any shot in what is now a wildly top-heavy division.

Needless to say, the D-backs’ rotations falls well behind that of the Dodgers and Padres within the NL West, but they’re far from the only team in baseball with that distinction.


  • Last Season: 88 wRC+ (26th) / .306 wOBA (T-24th)
  • Key Additions: INF Asdrubal Cabrera

After a fine showing from the offense in the 2019 season, the D-backs saw their offense plummet in the shortened 2020 campaign.

Ketel Marte turned in an MVP-caliber 2019 campaign that saw him post a 150 wRC+ across 144 games only to see that figure fall right out of the bottom all the way to a 94 mark in 2020. Without their lineup anchor, the D-backs couldn’t get much of anything going consistently and especially struggled against left-handed pitching with their 78 wRC+ against southpaws checking in at 26th league wide.

Cabrera was a late-season addition to help take second-base reps off the hands of Marte, who can now split time in center field as well with the likes of Tim Locastro (against lefties) as well as Daulton Varsho.

The team’s outfield is set with regulars David Peralta in left and Kole Calhoun in right, the latter coming off a team-high 125 wRC+ (min. 90 plate appearances) in his first season in the desert.

Arizona will also need veteran third baseman Eduardo Escobar to bounce back in a big way coming off a horrid 56 wRC+ with just four homers last season while catcher Carson Kelly will look to rebound from a tough sophomore campaign that saw him post a 70 wRC+ himself.

That’s a lot of ‘ifs’ for a team that didn’t bring in much at all to address one of the league’s weakest offenses from a season ago.


  • Last Season: 4.60 ERA (T-18th) / 4.83 FIP (25th)
  • Key Additions: Joakim Soria, Chris Devenski, Ryan Buchter

While Soria was the only one of the three new bullpen pieces to sign a Major League contract, the D-backs seemingly paid more attention to their bullpen than any other department on their roster

Gone is Archie Bradley from the closer role, so Soria could certainly be in line for some save opportunties given his 223 career saves between the Royals,  Rangers, Tigers, Pirates, White Sox, Brewers and most recently, the A’s.

Despite his tendency to bounce around the league at ate 36, Soria is coming off a 2.82 ERA/2.97 FIP with the A’s in 22.1 frames last season, although his tiny 3.1 Hr/FB clip yielded a 5.15 xFIP while his 4.36 SIERA also indicated some regression was likely on the horizon had it been a full seasons.

Arm injuries cost Devenski all but 3.2 innings in the 2020 campaign, and while much of his career ERA came from his rookie 2016 season, he owns a 3.35 ERA/3.53 FIP across 225 career MLB appearances, all but seven of which came out of the bullpen for Houston.

As for Buchter, the southpaw made just 10 MLB appearances last season with the Angels, posting a 4.50 ERA in the process. He’s been known to greatly outperform his peripherals, but posted an ERA between 2.75 and 2.89 between the 2016 and 2019 seasons while he owns a career 2.90n ERA, albeit with a 4.11 FIP and 4.77 xFIP.

Perhaps rightfully so, the D-backs didn’t spend big on their bullpen either with their playoff hopes all but already dashed for 2021.


The D-backs put forth one of the quietest offseasons in baseball this winter. Only Cabrera and Soria earned MLB contracts as free agents and there’s no guarantee Devenski or Buchter can crack the big-league roster out of spring training.

Rather, general manager Mike Hazen will allow his rotation and offense to iron out their kinks in 2021 and evaluate his club heading into the offseason.

Given what we witnessed from the 2020 World champion Dodgers and especially the Padres within the division this winter, it’s a predictable and understandable approach to not spend for the sake of spending as it’s quite agreeable the D-backs are well behind the top two clubs in the division at this juncture.

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Brenton Kemp / Author

Brenton is a lifelong sports fan who resides in Ontario, Canada. Brenton is a fan of most all sports but specializes in hockey, baseball, football, basketball, and golf. He’s a fierce researcher with a strong appetite to deliver accurate and relevant facts that in turn have led to past success with picks and DFS advice across the board. Brenton’s biggest goal is to deliver readers with the picks and advice that can build their bankroll. He takes great pride in his success and loves nothing more than to share that success for the benefit of everyone involved.