Infielder Jorge Polanco is beginning to move up the Twins' prospect list.

Polanco, a 19-year-old from the Dominican Republic playing in his first full-season league, is batting .347 with a homer and 25 RBI in 30 games at Class A Cedar Rapids. A switch hitter, Polanco is batting .560 against lefthanded pitchers.

"He can flat-out hit from both sides of the plate," Cedar Rapids manager Jake Mauer said. "He knows where the barrel is and he is still a young kid. He puts good at-bats together and can use the opposite field. When he starts developing, he will hit some balls that will go over the fence."

Polanco batted .223 in 2010 and .250 in 2011 with the Twins Gulf Coast League rookie team in Fort Myers, Fla. He began to break through last season at rookie league Elizabethton, batting .318 in 51 games.

With Cedar Rapids (22-9), Polanco shares middle-infield duties with Niko Goodrum and Candido Pimentel, so he gets to be the designated hitter at times. He has a strong arm, but the jury is still out on whether he will have enough range to stick at shortstop, where he started Friday, batting 2-for-4 with a walk, all while batting lefthanded.

"He's in the lineup pretty much every day," said Brad Steil, the Twins director of minor leagues.

Second time around

This will be a big month for Twins blue-chip prospects such as Miguel Sano (Class A Fort Myers), Eddie Rosario (Fort Myers), Byron Buxton (Cedar Rapids), Alex Meyer (Class AA New Britain), Trevor May (New Britain) and a few others.

Opponents will face them for the second time this season and approach them differently. If they continue to produce at a high level over the next few weeks, then some promotions could be handed out.

For instance, Mauer is interested how outfielder Adam Brett Walker II handles how teams pitch him again.

"The second time we face some of these teams, he's not going to get many fastballs," Mauer said. "He's going to have to make adjustments."

Walker, a third-round pick a year ago, is batting .305 with seven home runs and 33 RBI in 30 games.

Fort Myers infirmary

Seven players at Fort Myers landed on the DL in recent weeks. That includes righthander Madison Boer, a Eden Prairie product who broke his hand in an off-field incident; outfielder Lance Ray, who is battling a sciatic nerve problem; and infielder Adam Bryant, who recovered from an injury but separated his shoulder in his first game back.

That has opened the door for some prospects from extended spring training camp. Outfielder Jonathan Murphy, brother of Mets infielder Daniel Murphy, was batting .333 in his first six games since joining the Miracle.