IP | 2 |
---|---|
ERA | 9 |
WHIP | 1 |
BB/9 | 4.5 |
SO/9 | 18 |
- 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.
Top Rankings
Organization Prospect Rankings
-
BA Grade: 40/High
Track Record: Kempner was a standout at Gonzaga for three seasons before the Giants popped him in the third round of the 2022 draft. He signed for $525,000 and has spent the majority of his career pitching in a relief role. He moved from Low-A to Double-A in his first full season and finished the year with 78 strikeouts and 30 walks in 62.2 innings.
Scouting Report: Kempner’s aggression and arm action will relegate him to a bullpen role, where his pitch mix could be overpowering. The primary pieces of his arsenal are a mid-90s two-seam fastball and a sweeper slider in the low 80s that projects as plus. He also throws high-80s changeup, but it accounted for just 1% of his mix in 2023. He’s got a thick body with surprising twitch and can make hitters look silly when everything clicks. Kempner’s control is below-average, which might make the difference between which role he fills in the big leagues.
The Future: Kempner will likely return to Double-A in 2024, when he’ll look to tighten his control and improve his changeup enough to make it a viable third option. He’s a straight reliever who could fill an impact role with further development.
Scouting Grades Fastball: 60 | Slider: 60 | Changeup: 40 | Control: 40 -
BA Grade/Risk: 45/High
Track Record: Gonzaga provided a wellspring of talent in the 2022 draft, with its entire starting rotation plus outfielder Nick Morabito all going in the top three rounds. Kempner, who grew up in San Jose rooting for the Giants, was the last of the Bulldogs selected when he was drafted in the third round by his hometown team and signed for $522,500. Kempner made only nine starts for Gonzaga during the college season due to a finger injury, so the Giants took it slow and limited him to just nine innings after he signed.
Scouting Report: Kempner is a thick-bodied righthander who combines power stuff with a funk-filled delivery and sidearm slot. He works with a three-pitch mix, led by a darting, high-spin fastball that sits around 95 mph and touches 100. It's nearly a plus-plus pitch with its velocity, spin and life, but his command of it needs work. Kempner backs up his fastball with a potentially above-average slider with sweeping life and elite spin rates. He finishes his mix with a developing changeup in the high 80s that he threw sparingly in college and not at all as a pro. Kempner's high-effort delivery leads to scattershot control and command that will likely push him to the bullpen. He averaged more than six walks per nine innings at Gonzaga and had similar results in his pro debut.
The Future: Kempner will start for now projects to move to the bullpen, where he has a chance to flummox hitters with his fastball and slider. He'll head to High-A Eugene in 2023.
Scouting Grades: Fastball: 65. Slider: 55. Changeup: 45. Control: 40
Draft Prospects
-
School: Gonzaga Committed/Drafted: Never Drafted
Age At Draft: 21.1
BA Grade: 35/High
Scouting Grades: Fastball: 65 | Curveball: - | Slider: 55 | Changeup: 45 | Cutter: | Control: 40
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.
Scouting Reports
-
BA Grade/Risk: 45/High
Track Record: Gonzaga provided a wellspring of talent in the 2022 draft, with its entire starting rotation plus outfielder Nick Morabito all going in the top three rounds. Kempner, who grew up in San Jose rooting for the Giants, was the last of the Bulldogs selected when he was drafted in the third round by his hometown team and signed for $522,500. Kempner made only nine starts for Gonzaga during the college season due to a finger injury, so the Giants took it slow and limited him to just nine innings after he signed.
Scouting Report: Kempner is a thick-bodied righthander who combines power stuff with a funk-filled delivery and sidearm slot. He works with a three-pitch mix, led by a darting, high-spin fastball that sits around 95 mph and touches 100. It's nearly a plus-plus pitch with its velocity, spin and life, but his command of it needs work. Kempner backs up his fastball with a potentially above-average slider with sweeping life and elite spin rates. He finishes his mix with a developing changeup in the high 80s that he threw sparingly in college and not at all as a pro. Kempner's high-effort delivery leads to scattershot control and command that will likely push him to the bullpen. He averaged more than six walks per nine innings at Gonzaga and had similar results in his pro debut.
The Future: Kempner will start for now projects to move to the bullpen, where he has a chance to flummox hitters with his fastball and slider. He'll head to High-A Eugene in 2023.
Scouting Grades: Fastball: 65. Slider: 55. Changeup: 45. Control: 40 -
BA Grade/Risk: 45/High
Track Record: Gonzaga provided a wellspring of talent in the 2022 draft, with its entire starting rotation plus outfielder Nick Morabito all going in the top three rounds. Kempner, who grew up in San Jose rooting for the Giants, was the last of the Bulldogs selected when he was drafted in the third round by his hometown team and signed for $522,500. Kempner made only nine starts for Gonzaga during the college season due to a finger injury, so the Giants took it slow and limited him to just nine innings after he signed.
Scouting Report: Kempner is a thick-bodied righthander who combines power stuff with a funk-filled delivery and sidearm slot. He works with a three-pitch mix, led by a darting, high-spin fastball that sits around 95 mph and touches 100. It's nearly a plus-plus pitch with its velocity, spin and life, but his command of it needs work. Kempner backs up his fastball with a potentially above-average slider with sweeping life and elite spin rates. He finishes his mix with a developing changeup in the high 80s that he threw sparingly in college and not at all as a pro. Kempner's high-effort delivery leads to scattershot control and command that will likely push him to the bullpen. He averaged more than six walks per nine innings at Gonzaga and had similar results in his pro debut.
The Future: Kempner will start for now projects to move to the bullpen, where he has a chance to flummox hitters with his fastball and slider. He'll head to High-A Eugene in 2023.
Scouting Grades: Fastball: 65. Slider: 55. Changeup: 45. Control: 40