The Phillies’ Scott Kingery is rated the top prospect, while San Diego’s Luis Urias is second. Most of the top ten (seven) have played at AA or above, so they can be viewed as more major league ready than either of the Brewers’ representatives. The fact that Hiura and Diaz are rated so highly by MLB Pipeline is extremely encouraging, especially since they missed having anyone inside the top-10 lists for right-handed pitchers, lefties, catchers, and first basemen.
Brew Crew Ball voters selected Hiura as the Brewers’ third best prospect overall, and Diaz ended up as their ninth best this season, after finishing fifth last year. Diaz rates as the top power prospect at the position, and is tied for having the top arm. While Hiura isn’t top in anything, but his overall hit tool is very good, while his defense remains to be judged because of his elbow injury last year. He played DH in his final season at UC-Irvine, and only made it onto the field at the end of his stay at low-A Appleton. But he did handle his one chance flawlessly.
Hiura is the only first-round draft pick in the group. He didn’t disappoint in his first season of affiliated ball, hitting very well in both rookie league and at Appleton. He has shown good gap power and makes consistent hard contact. If the elbow continues to stay healthy, and Keston continues to hit, a late season appearance in 2019 for the Brewers isn’t out of the question.
Diaz has shown good power since coming to Milwaukee from Arizona after the 2015 season in the Jean Segura trade. He has 33 homers over the last two seasons, but his 2017 campaign at high-A Carolina saw a jump in his strikeout rate and a dip in his contact rates. He was hindered by a broken hamate bone in his right hand, which was treated surgically last September. His high rating on arm strength reflects his usage as a shortstop as well, and his left-handed bat will always be a plus. The presence of Hiura in the Brewers’ system would seem to put some pressure on Diaz to have a bounce-back season in 2018, but of course you can never have too many good prospects. If you can hit, you’ll find a place to play.
Does the depth in the minors at second have any impact on how the Brewers build their 2018 and 2019 rosters? Most likely it does. They can afford to add a veteran on a shorter-term deal while waiting for the arrival of Hiura and/or Diaz. Or the Brewers can go with players already on the roster - Jonathan Villar, Eric Sogard, and Hernan Perez - for the next two seasons and hope for a bounce back from Villar or platoon production from Soda Boy and LBR. Of course, another option is always available - prospect assets can help the team by bringing other players back in trades, too.