WATCH: Kyrgios calls umpire a potato in D.C.

An unpredictable Nick Kyrgios has advanced to the round of 16 in Washington after a 6-4, 7-6 (5) win over Gilles Simon. As always, the match was not without its excitement as Kyrgios earned the shot of the day nod for smashing his Yonex frame at 2-2 in the second set.

But he gave it to a young fan in the stands, so that salvaged the tension a little bit.

Then, the 24-year-old closed out the match whilst arguing with the umpire Fergus Murphy.

He had challenged an out call on his second serve his first match point at 6-4 in the tiebreaker, but Murphy didn't hear it and the double fault stood. Kyrgios had also had to change frames between serves when his string broke, adding to the tension (pun intended).

"You're a potato with legs and arms," Kyrgios told Murphy.

The Australian managed to survive the adversity when Simon netted a forehand.

Despite his antics, Kyrgios is still wooing fans in the U.S. capital. Practicing earlier on the hot day, he tossed some water bottles over the fence.

And he's still as active as ever on social media, posting this reaction to a story about Novak Djokovic's coach Goran Ivanisevic.

On Thursday, Kyrgios will take on Yoshihito Nishioka.