The battle for No. 1 in the Pepperstone ATP Rankings at the US Open is down to two players: Casper Ruud and Carlos Alcaraz.
When Ruud defeated Karen Khachanov in the US Open semi-finals, he eliminated Rafael Nadal from contention. If Alcaraz loses to Frances Tiafoe in tonight's second semi-final, Ruud will become the first Norwegian World No. 1 in Pepperstone ATP Rankings on Monday.
If Alcaraz reaches the championship match, Sunday’s final between the Spaniard and Ruud will be for a Grand Slam trophy and World No. 1.
Pepperstone ATP Live Rankings Round By Round
| Player | SF | F | Title |
| Casper Ruud |
5,460 | 5,850 | 6,650 |
| Carlos Alcaraz | 5,460 | 5,940 | 6,740 |
Ruud, who entered the tournament as World No. 7, is currently No. 1 in the Pepperstone ATP Live Rankings.
Alcaraz is trying to become the youngest No. 1 in Pepperstone ATP Rankings history. The 19-year-old can break the mark set by Lleyton Hewitt, who was 20 when he became World No. 1 in 2001.