In 2018, Horwitz batted .288/.386/.443 in 219 at bats, had 43 runs batted in (RBIs) (7th in the Conference) and 34 walks (9th; the same as his number of strikeouts), and was again named Big South Conference Second Team.[8][1] After the 2018 season, he played collegiate summer baseball with the Bourne Braves of the Cape Cod Baseball League.[9] In 2019 he batted .268/.392/.465 in 213 at bats, led the league with 49 walks (against only 29 strikeouts) and 7 sacrifice flies, had 49 runs (6th) and 10 home runs (7th), and was named Big South Conference Honorable Mention.[10]
Horwitz spent his first professional season in 2019 with the Rookie League Bluefield Blue Jays and Low–A Vancouver Canadians.[12] He batted a combined .307/.368/.440, as in 248 at bats he had 4 home runs, 52 RBIs, stole 5 bases without being caught, and walked 24 times (while striking out 30 times).[7] He played 26 games at first base, 18 games in left field, and two games at second base.[7] With Bluefield, he batted .330 (6th in the Appalachian League)/.395/.471, with 18 doubles (3rd), 49 RBIs (3rd), and 3 sacrifice flies (10th).[13] He was named a 2019 Appalachian League Post-Season All Star.[14] Horwitz did not play in 2020 due to the Minor League Baseball season being cancelled because of the COVID-19 pandemic.
Horwitz returned in 2021 to play for the now High–A Vancouver Canadians and for the Double–A New Hampshire Fisher Cats. He batted a combined .294/.400/.462, as in 405 at bats he had 12 home runs and 66 RBIs, and 70 walks (versus 68 strikeouts).[7] He played 85 games at first base, five games in left field, and one game at second base.[7] With Vancouver, he led the High-A West with 28 doubles and 70 walks (to only 66 strikeouts), and had a .401 on-base percentage (9th) with 65 runs (6th), 62 RBIs (5th), and 5 sacrifice flies (3rd).[15] He had a 28-game hitting streak, breaking a 60-year-old Northwest League/High A-West League record.[3][4] He was named the Northwest League’s 2021 Top MLB Prospect, and a Northwest League Post-Season All Star.[3][16]
After the season, Horwitz played for the Mesa Solar Sox in the Arizona Fall League, where he batted .375 (6th in the league)/.460(9th)/.484 in 64 at bats, with 4 stolen bases (9th in the league) without being caught, as he played 12 games at first base and two games in left field.[17][18][19] He was named an Arizona Fall League Rising Star.[14] MLB.com named him Toronto's #30 prospect.[20]
2022–23
Horwitz started 2022 with New Hampshire, and was named Eastern League Player of the Week on June 13.[21] In July, as he was among the Eastern League leaders batting .297(4th)/.413/.517 in 232 at bats, with 46 runs (4th), 19 doubles (4th), and 43 walks (5th), he was promoted to the Triple–A Buffalo Bisons.[14][21] In 2022, between the two teams he batted .275/.391/.452 in 403 at bats with 77 runs, 12 home runs, and 51 RBIs, while playing 73 games at first base and 20 games in left field.[22]
On November 15, 2022, Horwitz was added to the 40-man roster to be protected from the Rule 5 draft. He was optioned to Triple-A Buffalo to begin the 2023 season.[23]Baseball America named him the Jays’ #14 prospect.[24]
For the 2023 season with Buffalo in Triple A, he batted .337(9th in the International League)/.450(leading the league, and second in Triple–A baseball)[25]/.495 with a .945 OPS (2nd) in 392 at bats with 30 doubles (7th), 78 walks (4th) against 72 strikeouts, 6 sacrifice flies (4th), and 3 intentional walks (leading the league), while hitting .360 with runners in scoring position and primarily playing first base (at which position he was voted the league's best defensive infielder in a Baseball America poll of league managers).[25][26] His 16.1% walk percentage was 5th-highest in the league, and his 14.9% strikeouts percentage was 9th-lowest.[27] Against right-handed pitchers, he batted .368/.490/.556.[28] Horwitz was named the Bisons' 2023 team MVP.[25]
On June 16, 2023, Horwitz was promoted to the major leagues for the first time after outfielder Nathan Lukes was optioned to Triple–A.[29] On June 18, 2023, he made his MLB debut with the Blue Jays, and collected his first MLB hit off of Texas Rangers pitcher Jon Gray.[30] He hit his first major-league home run (a solo shot) in a 7-5 win against the Colorado Rockies on September 3, 2023. In 39 at bats for the Blue Jays he hit .256/.341/.385.[26]
In June 2023, when Spencer Horwitz was promoted to the major leagues, New York Mets Media Relations Director Jay Horwitz tweeted a photo of the two of them together, and jokingly captioned it "Congrats to my grandson Spencer Horwitz on his promotion to the Blue Jays. A proud grandpa Jay."[31][32] Although the two of them are not related.[32] Spencer said: “Jay was our public relations guy for Team Israel during the WBC.... And it just kind of blew up. A lot of people still come up to me and say, 'Hey, I know your grandfather really well.' Then everyone is a little disappointed when I tell them that (it’s not true)."[32]
2024
In January 2024, MLB Pipeline ranked Horwitz #9 on its Top 10 1B Prospects list.[33] He was optioned to Triple–A Buffalo to begin the 2024 season, where he batted .335(4th in the league)/.456(2nd)/.514/.970(7th) in 212 at bats, as he was leading the league at the time of his call-up in doubles (22).[34][35][36][37] Horwitz was called up to the Blue Jays on June 6, 2024, after the club designated Cavan Biggio for assignment.[38]
In 2024 for the Blue Jays, he batted .265/.357(11th in the AL of all batters with 350 plate appearances)/.433 with 46 runs, 12 home runs, and 40 RBIs in 328 at bats.[7] On defense, he played 41 games at first base and 39 games at second base, and was the designated hitter in 17 games.[7] Among AL rookies with 350 or more plate appearances, he was first in batting average and on base percentage, second in OPS (.790), low strikeout percentage (18.4%), and contact percentage (83.0%), and third in walk percentage (11.0%) and hit by pitch (7).[39] He earned a salary of $741,900.[7]
