Kevin Franklin, Junior Arias and Donald Lutz are locked in a three way tie. Jeremy Kivel was close but slipped back.
Franklin - 2nd round pick in 2013, 19 in 2014, played just a bit in the AZL. Needs to cut down his Ks but he wasn't overmatched, either. Tremendous power potential. RH third baseman.
Arias - 22 y/o outfielder with the legs to play CF, all the tools, in a season split between low and high A he showed his power (15 HRs) and speed (60 SBs) but struck out 132 times in 493 Abs with just 18 walks. Tantalizing what ifs with Junior.
Lutz - 25, signed as amateur FA in 2007. good arm, great power, moves better than expected for a big guy. Too many days on roster to keep rookie status. Closest of the three to the majors. Didn't fare too well in Cincy and had perhaps his most lackluster minor league season (but interrupted by his time with the big club which may have been a factor). Still, power is evident.