Novak Djokovic, the No. 1-ranked men’s tennis player, began his bid for the final leg of the Grand Slam with a 6-1, 6-7 (5), 6-2, 6-1 victory over Holger Rune in the first round of the U.S. Open on Tuesday night.

Rune, an 18-year-old qualifier from Denmark, was making his debut in a Grand Slam tournament. He is a dynamic, flashy player with explosive power and contagious energy. He not only won the second set, but he also got the crowd on his side in Arthur Ashe Stadium, the largest venue in tour-level tennis with its five tiers and 23,771 seats.