Toledo – Argenis Diaz (INF)
Diaz was an outstanding force for the Hens in May, hitting a robust .342 in 19 games (73 at-bats). Though he lacks power – just one double and one triple last month – Diaz found other ways to chip in, walking ten times and still driving in seven runs. His ten walks almost equaled his strikeout total (11) for the month, and pushed his on-base percentage all the way up to .422 and helped him creep over the .800 mark for OPS. A free agent signing during the off-season, Diaz is up to .314/.390/.364 on the year.
Runner-Up: Timo Perez (OF)
Erie – Francisco Martinez (3B)
As a 20-year old pushed aggressively to Double-A to start the 2011 season, Martinez struggled throughout April, hitting a paltry .179/.263/.284 in 20 games since that time, Martinez has made some dramatic adjustments at the plate and is now one of the offensive forces for the Seawolves. In twenty more games last month, Martinez ripped the ball with a .333 batting average and .526 slugging percentage. His three home runs in May gave him five for the season (he has since hit another one in June), setting a new career high in that category. Martinez is still extremely young and very raw, but he is adjusting rapidly and is now up to .270/.323/.439 in his first exposure to advanced pitching.
Runner-Up: Justin Henry (UT)
Lakeland – Brent Wyatt (OF)
Though Wyatt made a brief two-game cameo with Erie last month, his top notch performance was saved for the 22 games he turned in with the Flying Tigers. Wyatt followed up his .295/.404/.385 line in April with a .296/.469/.380 line during May. Wyatt is showing exceptional patience at the plate, amassing 20 walks to just 13 strikeouts last month while exhibiting an even 31:31 mark for the year. Wyatt also picked up four extra-base hits with two doubles and two triples to go along with chipping in three stolen bases in three attempts. Wyatt's approach at the plate is helping him excel in High-A and it may only be a matter of time before he gets an extended look in Double-A.
Runner-Up: Gustavo Nunez (SS)
West Michigan – Nick Castellanos (3B)
The Tigers top position prospect entering the year, fans may have been questioning that lofty status after an April performance that saw Castellanos hit a meager .179 in 19 games. That rough patch is all but vanished from memory at this point as Castellanos' performance over the last month has announced loudly that there was no reason to be worried. In 31 games in May, the 19-year old Castellanos ripped the ball to the tune of a .303/.347/.477 line in the always tough hitting environment of the Midwest League. His line was buoyed by seven doubles, three triples, and two home runs. While his season line still isn't as shiny as some fans might prefer for a top prospect, Castellanos is showing the advanced bat many projected and there are some rumblings that he could force a look with Lakeland later in the summer.
Runner-Up: Hernan Perez (2B)