Machado's arm strength stands apart from the rest on this list. He earns entertaining remarks from scouts when he unleashes throws from deep in the hole at shortstop, humming it across the diamond with enough velocity and accuracy to earn easy 7s from scouts, and the occasional 8. Harrison's raw arm strength stands a half-tick over plus and could play up more with improved footwork and more consistency.
Fuentes and Martinez can both show plus arms from the left side, though Martinez takes a little longer to get rid of the ball. Robbins has displayed a plus arm throughout his career and had aspirations of pitching at Washington State before he signed with the Tigers out of the draft. As a high school senior, the left-handed Robbins pitched at 86-90 mph.
Adames drew praise as an amateur for flashing a plus arm, and during his DSL season in 2013 scouts saw that type of arm strength more consistently. The Tigers have always praised Zambrano's ability to chuck it and stateside scouts finally got a clear picture of his above-average to plus arm during his GCL debut last summer.
Moises Bello (SS)
Zac Shepherd (SS)
A recent signing, Bello will show the occasional plus throw from shortstop, but more consistently shows an average to solid-average arm. Scouts believe he could show plus more consistently as he adds strength to his 16-year old frame, though he will be on the shelf for awhile after receiving a 50-game suspension for violating the Minor League Drug Prevention and Treatment Program. Shepherd, who should arrive from Australia soon, offers an above-average arm with occasional plus throws. Scouts in Australia believe he has the raw arm strength to own a true plus arm, but his arm slot and footwork are too inconsistent right now.