Two big arms are moving up Twins minor league ladder

Two big arms in the Twins’ minor league system are ready to take the next step, the Twins have decided.

Top pitching prospect Brusdar Graterol and fireballer Jorge Alcala are on their way to Triple-A Rochester, according to Betsy Helfand of the Pioneer Press. The Twins confirmed the promotions –slated for Monday — late Saturday night.

Graterol is considered by many to be the top pitching prospect in the organization. Jordan Balazovic might give him a run for that crown.

Reports this year have had Graterol topping 100 mph with his fastball this year, and one invested observer said that his slider also wows people. He’s spent most of his time this season in Double-A Pensacola, where he posted a 1.78 ERA in 50 2/3 innings, including a 49:21 strikeout-to-walk ratio. He started 9 games and came on in relief twice.

Alcala joined the organization in the Ryan Pressly as a product of Houston’s minor league pipeline. He too features a big fastball, and his Double-A ERA is much less eye-catching. He’s started 16 games and has a 5.78 ERA in 102 2/3 innings. He’s posted a 105:37 strikeout-to-walk ratio, and has bounced back and forth between starting and relieving.