Australian tennis player Nick Kyrgios made another controversial exit at the Shanghai Masters when he went down to an American qualifier on Monday.
"We don't really know and I don't think he really knows exactly what his potential is".
Federer was quoted by AFP as saying, "I think it's really up to him where he wants to go and what his potential really holds".
The Russian-born Aussie, back at the Hong Kong Open after losing last year's typhoon-delayed final, added of her compatriot: "He's different, he plays different and I guess when you come to watch him you never know what's going to happen".
But a sloppy service game down 4-5 cost Kyrgios the set and he unravelled from there amidst a stretch of five lost games.
As Klahn worked his way towards a win, his frustrated Australian opponent engaged in an argument with French umpire Damien Dumusois.
Australian tennis player Nick Kyrgios has found himself in hot water yet again, following a freaky outburst at the Shanghai Rolex Masters. for the fourth year in a row.
There was no controversy this time as the 23-year-old lasted just 78 minutes on the court, having been beaten 4-6 6-4 6-3 by American qualifier and world number 104 Bradley Klahn.
The talented but temperamental Kyrgios, who is ranked 38th in the world, has a chequered history with Shanghai.
Kyrgios then smashed an ace and turned to Dumusois to sarcastically ask "was that borderline poor?" and was rebuked.
In his first round encounter with Steve Johnson a year ago, Kyrgios received a warning for smashing two balls out of court in frustration and he walked away from the game entirely after losing the first set tiebreak. "Monday's controversy was also the second time within the last six weeks that Kyrgios" effort has been questioned by an official.
During last month's US Open, an umpire copped a ban after he gave Kyrgios a freakish mid-match pep talk.
Kyrgios is in a significant slump and now has lost the No.1 Australian ranking to Alex de Minaur.
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