Keep an Eye On: The Diamondbacks’ Peter O’Brien


Grading on the Curve has been taking a look at top prospects in spring training who have a legitimate shot at helping their respective teams much sooner than later. Today’s “Keep an Eye On” series heads out to the desert to take a look at the Arizona Diamondbacks possible catcher of the future. That future may be Opening Day.

Peter O’Brien was acquired at the 2014 trade deadline from the New York Yankees for Martin Prado. O’Brien is a basher, as his power is second to none in the minor leagues. His defense and plate discipline, however have plagued him throughout his early professional career. 

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The 24-year old catcher was a second round draft pick by the New York Yankees in 2012. His half-season debut showed off what O’Brien would become known for as belted 10 home runs in his 48 game stint with the Staten Island Yankees in Rookie Ball. He would also bat .202 while striking out 61 times in just 198 at bats.

2013 saw a huge improvement at the plate for O’Brien as he slashed .291/.350/.544 over Low-A Charleston and High-A Tampa en route to leading the Yankees’ farm system in home runs. He started the 2014 season in High-A Tampa but after an early Florida State League Player of the Week Award in April, he was quickly promoted to the Double-A Trenton Thunder in the Eastern League. O’Brien exploded at Double-A, smashing 23 home runs to go along with the 10 he had already hit in Tampa. He was a Mid-Season All Star and was invited to the MLB Futures Game.

He was then traded to the Diamondbacks. He would play well in a short stint at Double-A in the desert, but he would shine once again in the Arizona Fall League. He was named an AFL Rising Star for the second consecutive season and was one of 22 of the best prospects to earn AFL All-Prospect Team honors. The future star is trending in the right direction for certain.

Here’s what we know about O’Brien. He has a lot of Adam Dunn in him, which would make him more suited as a designated hitter back in the American League. He is closer to Mickey Tettleton than he is to Mike Piazza, as he can bash with the best, but his plate discipline leaves much to be desired. O’Brien does not like to walk: in 399 combined at bats last season he walked 21 times. He’s big power swing, as with most prospects in today’s baseball, lead to an incredibly high strikeout rate. He struck out a combined 111 times, meaning he struck out roughly once every three at bats.

His arm is strong, but, as MLBPipeline points out, he still struggles in how quickly he can move behind the plate, both in blocking balls and throwing out attempted base thieves. At 6 foot 3 and 215 pounds, he is not the slightest of foot, so despite experience at other positions, O’Brien’s best bet is to hone his catching skills and try to make an impact there.

What O’Brien does have going for him in the immediate future is the lack of experience on the Diamondbacks depth chart. Arizona traded away their longtime backstop Miguel Montero, leaving the inexperienced Tuffy Gosewisch and Oscar Hernandez on the depth chart. Neither have shown an exciting bat throughout their minor league careers, although both have shown a good ability to throw out base runners (Gosewisch threw out 23 of 45 runners his final full season in the minors and threw out 8 of 19 as a backup in Arizona last season) and solid defense behind the plate. How their defense translates over a full season in the majors will be the deciding factor on how long the Diamondbacks will hold O’Brien back.

O’Brien, currently the No. 9 prospect in the Diamondbacks system, will most likely take his talents to Triple-A to start the season. Should he continue to harness his power and hone his discipline at the plate, he could very well see the big leagues in 2015.

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