Jahvon Blair arrived to Georgetown as Patrick Ewing's first recruit, signed in April, 2017 following the decommit of Tremont Waters to Louisiana State the month prior. A two-star recruit from Brampton, ON averaging 23 points a game, Blair was Georgetown's first Canadian signee since center Pascal Fleury in 1990.

Blair played in all 30 games his freshman season, starting two, finishing fourth on the team in scoring and best among all guards. An All Big East freshman selection, Blair shot a team best 85 percent from the free throw line and scored a season high 21 points in a loss at Creighton.

Despite this momentum, Blair was moved out of the starting rotation for most of the next two seasons, playing behind Mac McClung. Blair's shooting numbers as a sophomore had decreased by half in 2018-19 and was hovering at less than three points a game when he came off the bench and turned in a 21 point, seven three pointer effort at SMU, tying a school record and providing additional run time as a reserve during Big East play. As Blair's minutes per game went up, so did his scoring, and when McClung left the starting lineup with a season-ending foot injury, Blair stepped up. The junior guard averaged 39.1 minutes a game in 11 starts, finishing the season with a 10.8 points per game average.

With McClung having transferred, Blair took hold of the starting role as a senior and never let up. After four games he was averaging over 20 points a game, a reflection not only of more confident three point shooting but one of the Big East's best free throw shooters. A 25 point, six assist game at St. John's was a career scoring high, and a 22 point game at Creighton led Georgetown to a rare win at Omaha. At the conclusion of the 2020-21 season Blair was sixth in the Big East in scoring, second in three pointers, third in free throws, and second in total minutes played. He finished his Georgetown career 39th all time in scoring with 1,120 points, third all-time in three pointers with 210, and seventh all time in free throw percentage at 83.3 percent.