In 2016 graduated from Martin County West High School in Sherburn, Minn....spent two seasons (2017-18) at North Iowa Area Community College...prior to the 2019 season transferred to Texas Christian University, where he was a teammate of LHP Nick Lodolo.
2023
Turned 25 years old on the fourth day of the season...Began the season at Louisville and in eight starts went 2-4, 6.62 before he joined the Taxi Squad in Colorado on 5/15...spent the rest of the season in the Reds' rotation...In the 3-1 win on 5/16 at Col, became only the 10th visiting pitcher to make his Major League debut with a start at Coors Field, the first since Hou’s José Urquidy on 7/2/19...Became only the fourth Reds pitcher to make his Major League debut with at least 5.2 innings, two hits or fewer allowed and at least 6 strikeouts, joining Tom Carroll (7/7/1974 vs StL, 7ip, 2h, 6k), Mo Sanford (8/9/1991 at SD, 7ip, 2h, 8k) and Johnny Cueto (4/3/2008 vs Ari, 7ip, 1h, 10k)...Became only the fourth Reds pitcher in the expansion era (since 1961) to retire at least 14 consecutive batters in his Major League debut, joining Wayne Simpson (16, 4/9/1970 at LAD), Rob Bell (16, 4/8/2000 vs Cubs) and Johnny Cueto (15, 4/3/2008 vs Ari)...In his debut, allowed a single to Charlie Blackmon, his first career batter faced, but didn’t allow another hit until Ezequiel Tovar’s solo HR in the sixth inning snapped the scoreless tie...Williamson retired 14 consecutive batters leading up to Tovar’s home run...first career strikeout victim was Mike Moustakas...On 6/26 at Bal walked his second batter, Adley Rutschman, to snap at 10.0 his consecutive innings streak without issuing a walk...Started the Reds’ 160th game of the season and kept their Wild Card chances alive with a 19-2 quality start win at StL...From 9/2-9/11 was on the COVID-19 injured list...after he was reinstated, went 1-1, 5.89 in his last four starts of the season...Twice picked runners off second base, KC’s Bobby Witt Jr. (PO/CS 145) and SD’s Fernando Tatis Jr. (PO/CS 165)...Once was called for a pitch timer violation, on 5/22 vs StL (Paul Goldschmidt batting)...Twice was called for disengagement violations, on 8/7 vs Mia (Jorge Soler batting, Jon Berti to second on the balk) and 8/29 at SF (Paul DeJong batting, J.D. Davis to second and Patrick Bailey scored on the balk)...Two of his starts were shortened by rain, a third was suspended & completed the next day and a fourth start was postponed & played the next day...In the top of the third inning on 6/26 at Bal did not return after a 1 hour, 44-minute rain delay...on 7/6 at Wsh, remained in the game following a 1-hour, 43-minute rain delay in the top of the second inning...pitched 3.0 innings...on 7/17 vs SF, the game was suspended with the score tied at 2-2 with one out in the eighth inning (completed the next day, 4-2 loss in 10 innings)...his start on 8/12 at Pit was postponed 49 minutes prior to the scheduled first pitch...was played the next day...Entered the season rated by Baseball America the 10th-best prospect in the organization.
2022
During spring training was acquired from the Mariners in the six-player trade that sent 3B Eugenio Suárez and OF Jesse Winker to Sea... After the trade, joined the Reds for the rest of Major League spring training camp... In his first season in the organization went 6-7, 4.11 in 27 starts for Class AA Chattanooga and Class AAA Louisville... Ranked among Reds minor league pitching leaders in starts (T1st, 27), innings pitched (3rd, 122.2), opponents' BA (3rd, .246), ERA (4th, 4.11), strikeouts (5th, 123) and WHIP (8th, 1.56)... Began the season at Chattanooga...on 6/28 was promoted to Louisville... Was added to the 40-man roster at the 11/15 restricted list deadline, along with IF Elly De La Cruz, RHP Ricky Karcher, IF Noelvi Marte, RHP Lyon Richardson and RHP Levi Stoudt.
2021
In 19 starts at Class A Everett and Class AA Arkansas combined to go 4-6, 3.39 ERA (98.1ip, 153k)...In 13 of his 19 starts recorded at least eight strikeouts...Averaged 14.0 strikeouts per nine innings, highest ratio among all Mariners farmhands and fifth-best in the minor leagues...Led Mariners minor leaguers in strikeouts (153) while ranking fifth in innings pitched (98.1)