The Argentine, surprise champion at the 107th US Open, summed up his win best by saying he had beaten the field but not the course.
J J Spaun drained an incredible 64-foot birdie putt that snaked across a sodden 18th green to win the US Open by two shots from Robert MacIntyre on Sunday.
The ace golfer had to settle for a card of five-over 75 to be tied 77th after the opening round of the US Open.
Nick Dougherty fired a two-under-par 68 to forge one shot clear in the US Open first round.
With a total of 10-over 150, the Indian ace is tied 51st, as 63 players made the cut.
Tiger Woods has registered to play in June's US Open at Oakmont Country Club in Pennsylvania but has not set a timetable for his return to the PGA Tour.
Experienced Indian golfer Jeev Milkha Singh will make his fifth appearance at the US Open next week after Thailand's Thongchai Jaidee withdrew due to personal reasons.