MLB Rookie Report: Dan Altavilla, RHP, Seattle Mariners

On Saturday the Seattle Mariners promoted rookie right-hander Dan Altavilla to the major league roster. Let's take a look at what he offers.

First, the basic background from the 2016 Baseball Prospect Book:

Dan Altavilla, RHP, Seattle Mariners

Bats: R Throws: R HT: 5-11 WT: 200 DOB: September 8, 1992

2015: Grade C

The Mariners drafted Alvatilla in the fifth round in 2014 from Mercyhurst College in Pennsylvania. He was reasonably effective in the California League last year, taking every turn and showing impressive durability despite his height; he is strongly built, so maybe it is really a case of "because of." He’s got velocity with a fastball up to 93-94 MPH. His slider flashes plus and he has a workable change-up. He could use tighter control, but overall he did pretty well, especially as a fly ball pitcher in the California League. With a bit more polish he could become a number four starter. Grade C+

ADDITIONAL COMMENTARY

Although used as a starter in A-ball, the Mariners shifted Altavilla to the bullpen this year for Double-A Jackson in the Southern League, with very positive results: 1.91 ERA, 65/22 K/BB in 57 innings, a mere 47 hits, a .196 average against, and 16 saves in 20 attempts. He throws slightly harder in relief and has been particularly deadly against right-handed hitters, holding them to a .155 average.

The main caution flag here is control: Altavilla's walk rate is higher than ideal, though his stuff was good enough that this did not hurt him against Southern League competition. That may or may not remain true in the majors, but he's been especially effective recently (1.55 ERA, 35/9 K/BB in his last 29 innings) and the Mariners are confident enough in his chances to open up a spot on the 40-man roster for him now, more than a year before when it would normally be necessary.