Fifita played sparingly in his first season at Arizona, serving as the backup to Jayden de Laura. Fifita made his collegiate debut on September 10, near the end of the fourth quarter of a 39–17 home loss to Mississippi State.[5] He went completed 4 of 8 passes for 56 yards.[5] Fifita threw his first career touchdown pass to high-school teammate Tetairoa McMillan in the fourth quarter of a 45–20 road loss to #14 Utah.[6]
Fifita began 2023 as a backup but stepped up in Week 4 after Jayden de Laura got injured, leading Arizona to a narrow win over Stanford.[7] He impressed in his first start against #7 Washington, throwing for 232 yards and three touchdowns, followed by a strong performance against #9 USC with over 300 yards and five touchdowns, earning Pac-12 Freshman of the Week honors.[8][9][10] Fifita won the award again after winning his first game as a starter the following week in a 44–6 rout of #19 Washington State in Pullman, Washington.[11][12]
After a bye week, Fifita started against #11 Oregon State, despite de Laura's recovery, and led Arizona to a 27–24 upset win with 275 yards and three touchdowns, earning his third Pac-12 Freshman of the Week award in October.[13][14] The following week, Fifita threw for 300 yards and three touchdowns in a win over #19 UCLA, making Arizona bowl-eligible and securing the program's first-ever three-game win streak against AP Top 25 teams.[15][16] After beating Colorado on the road, Fifita led a 42–18 rout of #22 Utah, as he finished with a QBR rating of 97.6.[17][18] Against Arizona State, he broke the single-game school record with 527 yards and five touchdowns in a 59–23 victory, improving their win streak to six games.[19]
On December 5, Fifita was named the Pac-12 Offensive Freshman of the Year, becoming the second player in school history to earn the award, joining J. J. Taylor.[20] Against #12 Oklahoma in the Alamo Bowl, Fifita threw for 354 yards and two touchdowns in a 38–24 comeback victory, concluding the season on a seven-game winning streak and securing the Wildcats' fourth ten-win season in program history.[21] Fifita finished the season tied for fourth in completion percentage (72.4) among qualified quarterbacks,[22] as well as the fifth-most passing yards (2,869), second-most touchdown passes (25), second-fewest interceptions (6), and highest rating (165.9) among qualified freshman quarterbacks in the FBS.[23]
Despite the departure of head coach Jedd Fisch, Fifita announced that he would return to Arizona for the 2024 season.[24] In the season opener against New Mexico, Fifita threw for 422 yards with four touchdown passes in a 61–39 victory.[25] After winning against Northern Arizona, Fifita and the Wildcats saw their nation-best nine-game winning streak come to an end on the road against #14 Kansas State. Fifita threw for 268 yards on 26-of-42 passing but was intercepted once and had zero touchdowns as they lost 31–7.[26]
Following a bye week, Fifita threw for 197 yards and two touchdowns against #10 Utah, including key third-down completions of 41 and 35 yards during a touchdown drive in the fourth quarter that kept the Wildcats ahead, winning 23–10 in Rice–Eccles Stadium.[27]