Here's his scouting report from Fangraphs' Kiley McDaniel:
The Scouting Report
Hit: 45/55, Game Power: 45/50+, Raw Power: 55/55, Speed: 55/55, Field: 50/50, Throw: 55/55, FV: 50
There’s undeniable talent here: Olivera has above average bat speed, bat control, plate discipline and raw power, which is to all fields and he has a history of getting to in games. He’s an above average runner that can play second base or third base and has an above average arm. That’s an above average everyday player with the statistical track record to give you some confidence that he’ll perform in the big leagues, but there’s real risk of him staying on the field regularly and not having his tools regress in a few years.
What all of this the means is that the optimistic outcome is, in 2015 in the big leagues, that Olivera could hit .260-.280 with a good OBP, 15-20 homers and solid-average base running and defensive value. He may well be better in 2015 than Yasmany Tomas and Rusney Castillo, but given his age and track record, that isn’t going out on much of a limb; the concern is if he’s better than them in the following years and the risk associated with that. It’s possible Olivera will need a couple week in the minors to get up to speed, but he’s seen as a plug-and-play MLB option.