By Rory Carroll
NEW YORK (Reuters) - Reilly Opelka scored the biggest upset of the U.S. Open so far on Monday, defeating 11th seed Fabio Fognini 6-3 6-4 6-7(6) 6-3 to win his first main-draw match at the tournament.
The 21-year-old American hit 26 aces and saved five of seven break points to come out on top of the slugfest, where his Italian opponent pounded 16 aces of his own.
Opelka looked like he would wrap up the match in straight sets but Fognini saved a match point and hung on to win the tiebreak to extend the contest.
Opelka, though, would not be denied, pumping his fist and applauding the crowd who backed him after he hammered a forehand winner, his 58th of the match, to seal the victory on a sun-soaked Court 17.
Next up for Opelka is a second-round meeting with qualifier Dominik Koepfer or Spaniard Jaume Munar.
(Reporting by Rory Carroll; editing by Clare Fallon)