D-backs slugging prospect O’Brien sharpens catching skills in Fall League

After hitting 34 home runs in the minor leagues this season, Peter O'Brien has kept up the pace with three home runs for the Salt River Rafters in Arizona Fall League play.

Mark J. Rebilas/Mark J. Rebilas-USA TODAY Sports

PHOENIX — When Peter O’Brien was 14 years old, he was 5-feet-4 and 125 pounds. It only seems that he swings a bat about that size these days.

O’Brien has been one of the most productive hitters in the game since a late-high-school growth spurt, and the Diamondbacks acquired him last summer with the belief it will continue.

O’Brien, who’s position of choice is catcher, is catching up on at-bats with the Salt River Rafters of the Arizona Fall League after missing the final month of the summer season with a left shin injury. The injury came just four games after he was acquired from the New York Yankees for Martin Prado and one game after his first home run at Double-A Mobile, his 34th homer of the season. 

 "I see a good hitter who is going to make an impact, a good splash at the big league level," said Jacob Cruz, D-backs minor league coach who is on the Rafters’ staff. "Personally, I see a 30-plus home run guy at the big league level.

 "There is something special about the way the ball comes off his bat."

 Reggie Jackson is on board. While with Trenton this summer, O’Brien hit a home run that not only cleared the 407-foot sign in center field but also went over the batter’s eye and the flagpole. Had Arm & Hammer Park been oriented differently, the ball might have landed in the Delaware River. When O’Brien returned to the dugout, Jackson was there to greet him.

 "He shook my hand and said, ‘That’s the best ball I’ve ever seen hit in the minor leagues.’ That was pretty cool," said O’Brien, who now checks in at 6-3 and 215.

 O’Brien had 10 homers in 30 games at Class A Tampa this season before being promoted to Trenton, where he hit 23 more homers in 72 games. He slashed .271/.316/.594 and finished with 23 doubles and 74 RBI. O’Brien averaged a home run every 11.7 at-bats this season, third in the minors behind slugging third base prospects Joey Gallo (42 homers, 10.4 ratio) and Kris Bryant (43 homers, 11.4).

 He has three home runs and seven RBI in 16 games for Salt River and has been invited to play in Saturday’s Rising Stars game. He also has drawn a league-high 14 walks, a point of emphasis as he attempts to become more selective at the plate. O’Brien has not walked more than 22 times in his two full minor league seasons. 

 With catchers Miguel Montero and Tuffy Gosewisch set to return for the Dbacks, it would be a stretch to see O’Brien open the 2015 season in the big leagues, even with his offensive resume.

 While production has been a constant, the other side of the ball remains a work in progress. O’Brien did not begin catching until his last year in high school at Miami Braddock High and played behind the plate regularly only in his three seasons at Bethune-Cookman University and a final year at Miami (Fla.). O’Brien played first base, third base and right field on his way up the Yankees’ chain, in part because the Yankees’ were brimming with catching prospects.

 The D-backs have told O’Brien that they consider him solely a catcher, although he has played some first base in the Fall League. O’Brien has spent extra time on his defense this fall, working on blocking, receiving and transferring the ball from glove to hand to facilitate his throwing to the bases. The lessons seem to be taking. O’Brien threw out three base runners attempting to steal Oct. 24, when Archie Bradley threw four scoreless innings in his best outing of the Fall League season.

 "I think I can receive and block with the best of them. The biggest thing has been throwing, and that’s what I’ve been working on the hardest," O’Brien said. "I think it is more of a transfer thing. Trying to find out where it is more comfortable for me and make sure I get the ball out clean so I can let my arm work. I think the feet are there. Even though you work on everything, the most important thing is just finding that consistency of getting the ball into my hand."

 Scouts have not been kind in evaluating O’Brien’s defense, and one said, "You like him for his bat."

O’Brien said he pays the criticism no mind.

 "I’ve never been one to take to heart or look too much into what other people say," he said. "I don’t really follow up on that stuff. I know what I can do. I know what I can do well. I know what I have to do to get there. Along with the help of coaches and teammates, if I put in the work ethic, I know I’ll be there."

 O’Brien has pushed forward before. Because he did not fill out until his junior year in high school, he was not highly recruited. He signed with Bethune-Cookman two weeks before the start of his freshman year, after its coaches saw him in a showcase late in the summer 2008. 

Personally, I see a 30-plus home run guy at the big league level. There is something special about the way the ball comes off his bat.

D-backs minor-league coach Jacob Cruz 

 "I worked out every single day in a gym, ate my parents out of house and home and got to about 6-2, 180 that year," O’Brien said of his growth spurt in high school.

 "That’s probably when everything kind of clicked together. That’s when I told myself this is really what I want to do for the rest of my life. I was going to bust my tail to get there. It was huge for me. A lot of motivation. Kind of seeing everything work together and start clicking was nice."

 O’Brien admitted the July 31 trade to the D-backs caught him off guard, but he embraces the opportunity.

 "I was a little bit shocked at first. There were rumors I was going to get traded, but you never believe it is going to happen until it happens," O’Brien said. 

 "After everything hit me and settled in, it was really exciting to have someone make a move like that for you and want you to be their guy. I am ready to work."

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