During DiVincenzo's second year in the league, he set career highs nearly across the board. The 6-foot-4 guard averaged 9.2 points, 4.8 rebounds, 2.3 assists and 1.3 steals over 23.0 minutes per game. The Villanova product appeared in 66 out of a possible 73 games, with 27 starts. He also shot 45.5 percent from the field, 33.6 percent from three and 73.3 percent from the charity stripe. During a win over the Clippers on Dec. 6, the sophomore swiped a career-high four steals, adding 11 points, five rebounds and one assist. Ten days later against the Mavericks, DiVincenzo posted career highs in both rebounds (10) and assists (nine) while also contributing five points, three steals and one block in the start. He would reach that rebounding mark again Feb. 24 in a win over the Wizards. On Dec. 22 in a win over the Pacers, DiVincenzo blocked a season-high two shots, and he reached that number again Jan. 14 in a win over the Knicks. The guard scored a career-high 19 points on Jan. 16 in a win over the Celtics, going on to match that mark again Feb. 12 against the Pacers. During the first round of the playoffs against the Magic, DiVincenzo averaged 5.6 points, 3.2 rebounds and 1.0 assists. During the second round against the Heat, he averaged 7.6 points, 3.2 rebounds and 1.4 assists. His best playoff performance was Game 5 against the Heat, where DiVincenzo finished with 17 points (5-9 FG, 3-6 3Pt, 4-5 FT), four rebounds, one assist and one steal. In the NBA ranks, DiVincenzo finished with the 10th-best steal percentage (2.6), the third-best defensive rating (101.3), the 15th-most defensive win shares (3.2) and the sixth-best defensive box plus/minus (2.4).

The 17th overall pick in the 2018 NBA Draft after three years at Villanova, DiVincenzo appeared in 27 games with the Bucks, seeing 15.2 minutes per contest. He averaged 4.9 points, 2.4 rebounds and 1.1 assists while shooting 40.3 percent from the field, 26.5 percent from three and 75.0 percent from the free-throw line. He may have had opportunities to appear in more games, though he dealt with a heel injury for a significant chunk of the season. Arguably his best performance of the season occurred during a 22-point victory over the Magic. DiVincenzo posted a career-high 15 points (6-9 FG, 1-4 3Pt, 2-2 FT) and three rebounds in only 18 minutes. His other career highs were, respectively, eight rebounds, five assists, three steals and two blocks. DiVincenzo was part of a very successful five-man lineup that was plus-35.5 points per 100 possessions in a 21-minute sample, and it included Eric Bledsoe, Khris Middleton, Ersan Ilyasova and John Henson. The Bucks' home court seemed to make DiVincenzo more comfortable, as he posted a better true-shooting percentage (54.8) and net rating (plus-3) than he did on the road. In the six games that DiVincenzo saw at least 20 minutes, he averaged 8.0 points and 3.5 rebounds while totaling a combined seven steals-plus-blocks. His most efficient month was March, when he shot 8-of-17 from the field and 5-of-14 from distance for an effective field-goal percentage of 61.8.