Roger Federer understands Dominic Thiem's frustration over his post-match news conference being interrupted to make way for Serena Williams, but he still found the situation funny.

World number four Thiem was midway through talking to the media when he was ordered to clear the room for Williams, the 23-time major winner having just lost 6-2 7-5 to Sofia Kenin.

The Austrian, a runner-up at Roland Garros last year, fumed: "I don't really get it, seriously. I mean, what the hell? It's a joke - I have to leave the room because she's coming?"

Federer suggested there must have been a communication breakdown and felt Thiem, who had beaten Pablo Cuevas in four sets to advance to the last 16, should have been given priority, but he found the way it played out humorous.

"I don't know what went wrong, but something went wrong for this to happen," said Federer after a straight-sets victory over Leonardo Mayer on Sunday sent him into the quarter-finals.

"I think with all the players there is always a way to go that the one who is still in the tournament gets priority. That's how I see it. If I would have lost against Mayer, I would let Mayer go first or decide when he wants to go to press as he's got a next match. My next match is far, far away. So that's just the way you go about it.

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

A post shared by Dominic Thiem (@domithiem) on

"Now, there must have been a misunderstanding or maybe they should have kept Serena still in the locker room, not waiting here in the press centre. I don't know exactly what happened.

"I understand Dominic's frustration. For him it's just about how in the world did this happen? I don't think he's mad at Serena or anybody. I just think it was an unfortunate situation that I thought was funny and we joked about it just before.

"That's why I'm very much aware of what happened, and that's why we are laughing in the locker room about it now. But in the moment, I understand [why he was] like, 'What is going on? It's a joke'.

"How he said it, it was great. I love his accent. In German, too, by the way, not just in English. And he knows that."