NEW YORK (Reuters) - Qualifier Botic van de Zandschulp sent Norwegian eighth seed Casper Ruud packing 3-6 6-4 6-3 6-4 in the second round of the U.S. Open on Wednesday, in the biggest upset of a tournament that has so far mostly gone to script.

Ruud overcame an early break to win the first set as van de Zandschulp struggled to get his first serves in but was left without answers as the Dutchman found his form and fended off all six break point opportunities in the third.