Sergio Alcantara

The Diamondbacks situation at shortstop is unclear.

When healthy, Nick Ahmed is the full-time starting shortstop. In spring training, Nick Ahmed’s shoulder has bothered him. The offseason injections of Platelet-Rich Plasma (PRP) and cortisone did not fix the shoulder. Apparently, a spring training MRI did not reveal any problem that surgery could correct.

Important questions must be answered soon. Will Nick Ahmed’s shoulder force him to play part time instead of full time? Will Nick Ahmed’s shoulder force him to the disabled list?

UPDATE from Torey Lovullo’s pregame media session on 30 March: Nick Ahmed got a couple more injections and is completely shutdown from all baseball activity for 10 days. After that Nick Ahmed will build from there. My view is he will almost certainly start the season on the disabled list.

Who will play shortstop if Nick Ahmed cannot be the full-time shortstop? Recently acquired Sergio Alcantara stands out as a candidate, along with Geraldo Perdomo who was impressive in September of last season.

Comparison of Sergio Alcantara and Geraldo Perdomo at shortstop.

Sergio Alcantara had the better arm strength (70 vs 55 scouting rating). A further indication of arm strength is that in September of 2021 he pitched to one batter and got a fly out.

Which player was the better defender as shortstop depends on which metric you choose. If you look at 2021 Outs-Above-Average (OAA), Sergio Alcantara was the better defender (6 OAA in 388.1 innings at SS compared to 0 OAA in 81.1 innings at SS). Instead, if you look at Defensive Runs Saved (DRS) Geraldo Perdomo was the better defender (1 DRS in 81.1 innings at SS compared to 2 DRS in 388.1 innings at SS).

Looking at 2021 OPS+ shows that Geraldo Perdomo was a better batter than Alcantara and Ahmed.

• 117 OPS+ Geraldo Perdomo
• 71 OPS+ Sergio Alcantara
• 67 OPS+ Nick Ahmed

Sergio Alcantara has strengths and weaknesses.

Interestingly, Sergio Alcantara improved his batting in 2021 in two measures:

• His OPS+ improved from 60 to 71.
• His hard hit percentage increased from 23.6% to 33.6%.

Perhaps accepting he will never be a power hitter, in 2021 he seems to have changed his swing so his average launch angle decreased from 21.5 degrees to 10.5 degrees. Perhaps the Diamondbacks hitting coach could further improve his hitting because the ideal launch angle is 15 to 20 degrees. Even with a further improvement, it’s likely that Alcantara’s batting will not reach the level of Perdomo.

Sergio Alcantara has potential at shortstop per the following quotes:

In October of 2016, Eric Longenhagen of FanGraphs wrote about Sergio Alcantara.

“Alcantara has a 70 arm, is an above-average runner and plays an adequate defensive shortstop. A switch-hitter, his swing is better from the right side where he has better barrel control, is quicker into the hitting zone and integrates more explosion from the lower half.” — Eric Longenhagen

In March of 2017, Michael McDermott of AZ Snake Pit wrote about Sergio Alcantara.

“A switch hitter with little pop, his offensive ability has to rely on getting on base and using his speed to create runs on the base paths.” — Michael McDermott

In April of 2018, Jim Bowden wrote about Sergio Alcantara.

“Alcantara is an above average defensive shortstop with a plus plus arm. He’s only an average runner but makes up for it with a good first step and smart positioning. His range and hands are both solid. He needs to use his lower half more at the plate, but is definitely making progress. He should be ready to be the Tigers every day shortstop sometime in 2019.” — Jim Bowden

In 2018, the GM for the Tigers talked about Sergio Alcantara.

“He is only 21 years old and has hit well in his first taste of AA. We really like his actions at shortstop and his plus arm strength.” — Al Avila, GM for Tigers

If Nick Ahmed cannot play shortstop, could Alcantara and Perdomo platoon at shortstop?

In 2016, Jeff Wiser of Inside the Zona wrote about Sergio Alcantara. If Alcantara and Perdomo platoon at shortstop, then his words were prescient.

“Long term, he’s likely best as a backup shortstop off the bench as a strong fielder. The bat could change [for the better] but don’t hold your breath.” — Jeff Wiser

In 2021, Sergio Alcantara’s splits (255 PAs) showed:

• His OPS was better against right handed pitchers (OPS of .720 vs .435).
• His OPS was better as a substitute instead of a starter (.705 vs .622).
• His OPS was better as a pinch hitter (.970).

His splits support the idea of a platoon with Perdomo regular starter (he hits well against left handed pitchers and right handed pitchers) and Alcantara as a substitute/pinch hitter.

UPDATE from spring training game on 30 March: Geraldo Perdomo entered the game in Daulton Varsho’s spot in the ninth inning. He hit a homer showing that like Alcantara he would be an excellent substitute/pinch hitter.

What if Nick Ahmed plays shortstop part-time?

If Nick Ahmed plays part time, that leaves playing time for either Sergio Alcantara or Geraldo Perdomo. Focusing on future seasons, Perdomo at 22 years old (3.3 years younger than Alcantara) would benefit most by further developing his skills with daily playing time in the minors. With that focus, Sergio Alcantara would play in the Majors until Geraldo Perdomo is fully ready for promotion.