• Full name William McCullough Kempner
  • Born 06/18/2001 in San Jose, CA
  • Profile Ht.: 6'0" / Wt.: 222 / Bats: R / Throws: R
  • School Gonzaga
  • Drafted in the 3rd round (106th overall) by the San Francisco Giants in 2022 (signed for $525,000).
    View Draft Report
    Kempner is a large and filled-out, 6-foot-2, 222-pound sidearm righty who attacks hitters from a unique, low release point. His stuff plays up thanks to that unique angle and funky delivery, but it’s not like he gets by on pure deception, as his fastball sits in the 93-95 mph range and has been up to 99-100 mph this spring. A low-80s slider has been his best swing-and-miss pitch this spring, though it’s an inconsistent breaking ball and might always be given his arm slot. Still, it is a pitch that has earned plus grades when it is on. He also throws a firm changeup in the upper 80s that has lots of arm-side life but could use more velocity separation. Kempner missed almost two months of the season with injuries this spring and logged just 36 innings in eight starts, but he posted a 3.00 ERA and struck out 48 batters (30.4 K%) while walking 21 (13.3 BB%) when he was on the mound. His control likely limits him to a relief role at the next level, but he’s got the stuff and unique arm slot to profile nicely there.

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Career Transactions

  • RHP William Kempner assigned to Eugene Emeralds from San Jose Giants.
  • Eugene Emeralds activated RHP William Kempner.
  • RHP William Kempner assigned to Eugene Emeralds from San Jose Giants.

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