In April, 2016, Baseball America rated Ona as the 6th best prospect in Cuba.
This was an aggressive grade, considering his age (19) and lack of Serie Nacional (think Cuban MLB) experience. But what scouts did see of him, mostly while he was playing in Cuba’s junior national leagues and the COPABE 18U Pan American Championship in Mexico, impressed them.
Ona is big (6’2″) with a compact swing that generates plus power. Mostly scouting reports said he has a mature approach at the plate–with the caveat that the scouting community has never really gotten an extended look at him.
He would easily of been selected in the first round of the 2016 draft if available.
The Padres jumped on him in 2016, signing him for $7 million. He signed in time to get some Instructional League time under his belt, and I imagine will open 2017 in affiliate ball.
He should open the season as one of the Padres Top 10 prospects. He has a way to go before he is going to help out the big league club, but if his potential is realized, he could be special.