Sitkowski opened his true freshman season in 2018 as Rutgers starting quarterback ahead of their season opener.[6][7] In Sitkowski's first start he completed 20 of his passes for 205 yards with a touchdown and three interceptions, as he helped Rutgers to a win over Texas State.[8] In week seven of the 2018 season, Sitkowski had an abysmal performance completing just two of his sixteen pass attempts for eight yards and four interceptions, in a loss to Maryland.[9] Sitkowski finished the 2018 season completing 134 of his 273 pass attempts for 1,158 yards and four touchdowns to eighteen interceptions.[10] Heading into the 2019 season, Sitkowski was projected to be the team's starting quarterback but lost the job to McLane Carter.[11][12] Sitkowski made his first start of the 2019 season in week four after starter McLane Carter went down with a concussion. In his start, Sitkowski completed 23 of his 33 passing attempts for 304 yards and a touchdown with an interception, in a 30–16 loss to Boston College.[13] However after just making one more start against Michigan, Sitkowski decided to redshirt for the rest of the 2019 season.[14][15] After the conclusion of the 2019 season, Sitkowski decide to enter the NCAA transfer portal.[16][17] However, he decided to enter the NCAA transfer portal and return to play for the Scarlet Knights in 2020.[18][19] Sitkowski made his first start of the 2020 season in week seven versus Purdue.[20] In his start he completed 18 of his 27 passes for 141 yards and two touchdowns, as he led Rutgers to an upset win over Purdue.[21] He finished the 2020 season going 52 of 82 on his passes for 44 yards and three touchdowns, while also adding two rushing yards.[22] After the conclusion of the 2020 season, he entered the NCAA transfer portal.[23][24]
Illinois
Sitkowski decided to transfer to play for Illinois.[25][26] Sitkowski made his Illinois debut in week one after starter Brandon Peters went down with an injury. Sitkowski completed 12 of his 15 passes for 124 yards and two touchdowns, as he helped lead the Fighting Illini to a 30–22 win over Nebraska.[27] Sitkowski was named the team's starter for their week two matchup versus UTSA.[28] In his start he threw for 266 yards and three touchdowns, but Illinois lost to UTSA.[29] In week nine of the 2021 season, after Sitkowski helped the Fighting Illini upset #7 Penn State in the longest game in NCAA history it was revealed, Sitkowski broke his arm and would miss the rest of the 2021 season.[30][31] Sitkowski finished the 2021 season completing 74 of his 148 pass attempts for 704 yards and six touchdowns with two interceptions, while also adding 31 yards on the ground.[32] In week six of the 2022 season, Sitkowski entered the game after starter Tommy DeVito went down with an injury. Sitkowski completed 13 of his 19 passes for 74 yards and an interception, as he helped Illinois to a 9–6 win over Iowa.[33] In Sitkowski's final season he completed 18 of his 25 pass attempts for 103 yards and an interception, while adding 18 yards on the ground.[34]