The American reached the second round of the tournament for the first time in two years.
John Isner is into the second round of the US Open for the first time in two years after beating the Argentinian qualifier Federico Delbonis in straight sets 6-3, 6-1, 7-5 in one hour and 53 minutes.
The Greensboro, North Carolina native served 19 aces and won 88% of his first serve points.
The world number 48 managed to get the first break of serve in the third game of the first set and from there it was smooth sailing as he served out the first set in 33 minutes.
The second set stayed on serve for the first two games before once again the American was able to get the break and managed to turn that break into a double break which was enough to take the second set.
The third set which was the most competitive of the three that were played stayed on serve until 6-5 when once again it was the world number 48 breaking serve to seal the match and the win.
The American will either face the German Peter Gojowczyk or the Dane Holger Rune in the next round.
In other results there was also wins for Grigor Dimitrov who thrashed Steve Johnson with the loss of seven games. Richard Gasquet and Brandon Nakashima also advanced to the second round with wins over Taro Daniel and Pavel Kotov respectively.
