William Kempner #33

Son of Mary Ann Kempner. Has two siblings, Sam and Katherine...Was a business major at Gonzaga University, where he pitched to a 6-4 record and 3.43 ERA (32 ER/84 IP) with 59 walks against 84 strikeouts during three seasons (2020-22)...Attended Valley Christian High School in San Jose, Calif., where he was named to the All-League First Team.

2025

Combined to go 7-3 with a 2.26 ERA (17 ER/67.2 IP) in 48 relief appearances between High-A Beloit (19 appearances), Double-A Pensacola (16) and Triple-A Jacksonville (13) during his first season in the Marlins organization...Totaled a career-high 95 strikeouts, the second-most among Marlins' Minor League relievers behind only RHP Josh White. Also ranked second in K/9 (12.64), IP (67.2) and appearances (48)...Among Marlins' Minor League relievers with at least 60 innings pitched, he ranked second in ERA (2.26) and fifth in WHIP (1.15)...Acquired by Miami from San Francisco on Jan. 15 in exchange for future considerations (International bonus pool money)...Started the year at High-A, holding opponents scoreless in 15 of his 19 outings and converting six of six saves...Allowed 10 walks against 39 strikeouts in 26.2 innings from April 5-June 7...Earned promotion to Double-A on June 10, where he posted a 1.13 ERA (three ER/24.0 IP), 1.08 WHIP and held opponents to a .139 AVG (11-for-79) in 16 appearances from June 12-Aug. 9...Finished the season with the Triple-A National Champion Jacksonville Jumbo Shrimp, going 3-0 with a 2.65 ERA (five ER/17.0 IP), one save, 15 walks and 25 strikeouts...Recorded at least one strikeout in 12 of his 13 appearances with Triple-A Jacksonville; recorded multiple strikeouts in six of those outings...Made two scoreless appearances (3 IP) with six strikeouts during the playoffs with the Jumbo Shrimp, including two hitless innings with three strikeouts in the Triple-A National Title game on Sept. 27 at Las Vegas.

2024

Missed the entire regular season on Double-A Richmond's injured list...Entered the year ranked as San Francisco's No. 29 prospect by Baseball America...Pitchers for the Scottsdale Scorpions in the 2024 Arizona Fall League. Made four appearances in relief, posting a 7.36 ERA (three ER/3.2 IP) and allowing two hits and three walks with seven strikeouts.

2023

Entered the season as San Francisco's No. 26 prospect by Baseball America...In his first full professional season, went 4-5 with a 3.73 ERA (26 ER/62.2 IP), 30 walks and 78 strikeouts in 38 appearances (five starts) between Single-A San Jose (14 games), High-A Eugene (23 games) and Double-A Richmond (one game)...Started the season in San Jose's rotation, making five consecutive starts and posting a 5.00 ERA (10 ER/18.0 IP) with 10 walks against 19 strikeouts...Posted career best 4.31 BB/9 and 2.60 K/BB rates.

2022

Made his professional debut with the ACL Giants Black on Aug. 17 (1.0 IP, three H, one R/ER, three K)...In five total appearances between the ACL Giants Black (two games) and Single-A San Jose (three games), went 1-0 with a 5.00 ERA (five ER/9.0 IP).