Zion Williamson towered over the college basketball season from the moment he put on a Duke uniform. His mind-bending combination of power, athleticism, and smarts captivated the country and reduced NBA general managers to yearning admirers praying to hit the lottery. Almost immediately, it became apparent June’s NBA draft would be all about Williamson with a massive gap between him and any other player.

It wasn’t always that way, though. As Williamson entered college, almost no one had him No. 1 overall on early draft boards. Duke did have the consensus top pick in the next draft on its roster, but it wasn’t Zion. It was his teammate R.J. Barrett.

Barrett was such a prodigious prep star that he was ranked No. 1 in two separate high school classes. He was unanimously considered the No. 1 player in the 2019 high school class before reclassifying up a year and earning the same honor with the 2018 group. Williamson’s high school ranking, conversely, was all over the map: ESPN had him No. 2, Rivals had him No. 5, and 247 Sports had him No. 7, below Kentucky’s E.J. Montgomery.

If Williamson so quickly became the No. 1 NBA prospect once he arrived at Duke, why was Barrett considered the superior recruit? There are a few different reasons.

Barrett starred at FIBA events Zion never played in

FIBA youth tournaments offer players the opportunity to test themselves in a high-stakes environment against international competition with statistical tracking. R.J. Barrett built his reputation at these events while playing for his home country of Canada. Zion Williamson never competed in a FIBA tournament for USA Basketball.

Barrett first competed on the global stage as a 14-year-old playing up at the U16 FIBA Americas tournament in Argentina in 2015, where he led the team in scoring despite being the youngest player on the roster. He did it again at the U17 FIBA World Championships in Spain a year later, averaging better than 18 points per game.

Barrett would have the defining moment of his prep career the next summer when he led Canada to victory over John Calipari’s U.S. team in the semifinals over the U19 FIBA World Cup in Egypt. All Barrett did in that game was go off for 38 points, 13 rebounds, and five assists.