Juan Martin del Potro has two free days before he plays another US Open semi-final, but light-heartedly revealed he intends to avoid his exuberant band of supporters in New York.

One of the most enjoyable aspects of Del Potro's run to the last four at Flushing Meadows, besides the joy of seeing this magnificent player fit and able to shine on the biggest stage once again after years of injury troubles, has been the presence of a small group of the Argentinian's friends from his hometown of Tandil.

Del Potro's vocal fans made themselves heard once again on Arthur Ashe Stadium on Tuesday as their hero ousted home favourite John Isner 6-7 (5-7) 6-3 7-6 (7-4) 6-2.

In an on-court interview with ESPN following his win, the 2009 champion was asked if he planned to spend time with his friends in the spare time before Friday's last-four matches, when he will face defending champion Rafael Nadal or Dominic Thiem.

"If I meet them, it is dangerous for me," said Del Potro with a grin.

"I will stay resting in my hotel, then afterwards we will have a chance to have fun together.

"They come all the way here from Argentina, paying for the flights, hotel, food, beers! They are so good."

Should Del Potro face Nadal again in the last four, it would be a rematch of their 2017 semi-final that the Spaniard won in four sets.