Dariel Alvarez

Orioles minor leaguer Dariel Alvarez with the High-A Frederick Keys last season. (Tim Jacobsen / Frederick Keys / August 21, 2013)

When Cuban outfielder Dariel Alvarez arrived in Bowie last year for the last few weeks of the Baysox season, manager Gary Kendall and hitting coach Butch Davis saw a player who was trying to fit a season's worth of slugging into a couple of home stands.

With a calm off-season and a sense of comfort gained with the staff in Bowie, Alvarez has become one of the Orioles’ top hitting prospects and, in one scout’s eye, one of the best sleeper prospects in all of baseball.

“He certainly isn’t a finished product,” Kendall said last week . “He has good nights, he has bad nights, occasionally. But all indications are that he’s playing real good baseball right now, and we’re lucky to have him.”

Alvarez, who was signed last year out of Cuba for $800,000, is hitting .326 with an .895 OPS and 10 home runs in 54 games. The most recent of those home runs, a solo shot Saturday night against Richmond, was representative of the most important adjustment he has made since last season.

The Cuban outfielder hit like crazy last summer in 39 games in High-A Frederick, with a .436/.463/.641 slash line and a pair of home runs. But when he arrived in Bowie, he was pressing too hard to replicate that. He hit .194 in nine games for Bowie last year.

In my several looks last year, Alvarez uncorked his swing so early that he was often left flailing at breaking pitches that fell out of the zone. Kendall referred to it as Alvarez “trying to hit the ball as soon as it came out of a guy’s hand."

“He tried to show his ability, but he was just really jumpy, excited,” Davis said. “He just couldn’t stay back and allow the ball to travel to him.”

In spring training, Davis said they showed him video of his at-bats from Bowie and gave advice that has led to Alvarez’s explosion.

“We … tried to get him to understand with the quickness of his hands, he doesn’t have to go out and get the ball,” Davis said. “He can let the ball travel and go out and be quick with his hands.”

By allowing the ball to travel further before swinging, Alvarez is better able to pick up the spin of breaking balls and doesn’t chase balls out of the zone. He’s also able to see fastballs better and get better wood on them.

Alvarez did just that Saturday, when he sat back on a 96-mph, 2-1 inside fastball and blasted it to dead center for his 10th home run of the season.

He also struck out twice on Sunday, which is representative of what the ultimate knock on Alvarez may be as a prospect. After striking out just six times in April, the free-swinging Alvarez fanned 19 times in 30 May games.

Alvarez hasn’t chased as much out of the strike zone as he did last year, but he doesn’t let a strike go without taking a hack. His quick bat allows him to be able to get to most pitches, but as he advances to face craftier Triple-A pitchers, and potentially, big league arms, Alvarez’s selectivity will be a challenge.

Several scouts have commented to me that Alvarez looks quieter and more relaxed at the plate this year, compared to last year. Kendall, who also managed Alvarez in the Arizona Fall League, said such adjustments would have come last season if Alvarez had more time.

“It’s not much of a difference in him offensively, because I think over the long haul, we probably would have saw what we’ve seen this year, because that’s what he showed in Frederick last year,” Kendall said.

jmeoli@baltsun.com

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