Renato Nunez, Daniel Robertson top Athletics system after big trade

The big Jeff Samardzija trade with the Chicago Cubs cost the Oakland Athletics a pair of strong prospects in shortstop Addison Russell and outfielder Billy McKinney. There is still some high-ceiling talent in the system however, notably third baseman Renato Nunez and shortstop Daniel Robertson. I had Robertson rated fourth and Nunez rated fifth on my pre-season Oakland Athletics Top 20 Prospects List (Russell was one and McKinney was two). Both holdovers are having fine seasons for High-A Stockton in the California League. Here's an update.

Renato Nunez, 3B: Signed out of Venezuela in 2010 for $2,200,000, Nunez is 20 years old, a right-handed hitter, listed at 6-1, 185. In 2013 he hit .258/.301/.423 with 19 homers, 28 walks, and 136 strikeouts in 508 at-bats for Low-A Beloit in the Midwest League. The home runs accorded with scouting reports about his power potential, but his poor on-base percentage limited his wRC+ to just 102.

2014 has been much better: he has a .287/.354/.554 line for Stockton, with 20 homers already, 25 walks and 67 strikeouts in 314 at-bats for a wRC+ of 132. Yes, the Cal League is an easier hitting environment than the Midwest League but reports indicate genuine improvement in his approach and his BB/K ratio is certainly much more attractive, adding objective weight to the subjective impressions. Most of his power still comes when he pulls the ball, but the spray charts are not as extreme this year.

He has also shown dramatic defensive improvement, improving his fielding percentage from a dismal .884 to a much more acceptable .933 mark this season. He has always shown a third base quality arm, but poor footwork and trouble with routine plays were huge problems in the past. Nunez is never going to have the range to be a gold glove type but this steadier play makes it more likely that he can stick at the position, at least in the short run, if he hits as anticipated.

Daniel Robertson, SS: Drafted in the supplemental first round in 2012 from high school in Upland, California, Robertson hit .277/.353/.401 with nine homers, 41 walks, and 79 strikeouts in 401 at-bats for Beloit in 2013. He didn't show as much power as Nunez, but more balanced hitting skills and on-base ability gave him a better wRC+ at 116. Like Nunez, Robertson has improved in '14, hitting .299/.402/.471 for Stockton with 49 walks and 56 strikeouts in 344 at-bats, resulting in a 133 wRC+.

Like Nunez, Robertson is age 20 (they were born within two weeks of each other in 1994) and listed at 6-1, 185. Despite those similarities, Robertson has less raw power than Nunez but is hardly punchless and is more of an all-field hitter. He does a particularly good job against left-handed pitching (.981 OPS this year). Reports continue to praise his short, efficient swing and ability to handle both fastballs and breaking balls.

The big question for Robertson: can he stay at shortstop? He's spent most of his innings there this year and has performed well in terms of avoiding excessive errors, but some continue to question if his range will hold up long-term. He's played a handful of games at second base and shortstop and acquitted himself well in both spots, so if shortstop doesn't work out other options are available.

That said, I would leave him at short as long as possible if I were Oakland. He's a lot more reliable than most 20 year old infielders, his instincts draw praise, and I suspect that his glove is under-estimated. You don't have to be Ozzie Smith to be valuable, and a shortstop who provides OBP, gap power, and decent defense as Robertson projects to do can hold a job for a long time.