'Say it to my face': Kyrgios explodes over rival's nasty sledge

Nick Kyrgios has ramped up his war of words with Casper Ruud after the Aussie's rival branded him an "idiot" during a recent interview.

The bad blood between the pair stems from their only head-to-head encounter at the Rome Masters in May.

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Kyrgios was infamously disqualified from the match against Ruud, prompting an angry exchange between both players.

The Aussie was stripped of the ATP points he’d earned in Rome, with Ruud insisting the punishment was too light.

“I’m not the only one who thinks he should be suspended for at least half a year," he said at the time.

Kyrgios then laughed at Ruud when video was posted online of the Norwegian celebrating the fact that Kyrgios had been disqualified.

Responding to the dig from Kyrgios on Wednesday, Ruud labelled the Aussie an idiot.

"I saw that he wrote a little about (my celebration)," Ruud said in an interview with Alex Theodoridis of Tennisportalen.

"Okay, he was disqualified but if we look at the head to head between me and Kyrgios, then it stands 1-0 to me.

"Does that mean I've won against him? It still stands 1-0 to me.

“He was completely crazy when I met him. It was nice to win. Whether I celebrated after the game or not? I do not care.

Nick Kyrgios and Casper Ruud have exchanged unpleasant words about one another. Pic: Getty

"I was happy and got 90 points and $50,000 in prize money so why wouldn't I celebrate?

"It's his problem that he's an idiot on the court."

Ruud's comments prompted a fresh response from Kyrgios on Thursday, with the Aussie taking aim at the Norwegian in a pair of social media posts.

The 24-year-old challenged Ruud to "say it to my face" next time he wanted to criticise him and accused his rival of only mentioning his name as a way of remaining relevant.

Kyrgios back in Davis Cup fold

Meanwhile, Australian captain Lleyton Hewitt says he’s prepared to overlook the most recent spate of bad behaviour by Kyrgios, saying the firebrand has earned his recall for the revamped Davis Cup finals.

Kyrgios is serving a six-month probation period for his spectacular meltdown in Cincinnati in August and subsequently branding the ATP corrupt at the US Open.

But his suspended sentence only applies to the ATP Tour and not Davis Cup.

Hewitt said the 24-year-old Kyrgios had done enough to work his way back into the team for the November tournament after he was overlooked for the qualification tie when he failed to meet new performance and behavioural standards.

"I have been watching that closely," Hewitt said of Kyrgios, adding the suspended ban hadn't affected his decision.

"I feel like on the Davis Cup court he's done absolutely everything I've needed in the past; he hasn't put a foot wrong.

"There's a lot of things he does in a team environment that I actually think we will see the best of him."

Hewitt said the world No.30 made contact with him in March to talk about how he could get back in Australian colours.

"We sat down in Indian Wells and went through things and he's been so willing to do whatever it takes to get back into the Davis Cup team," Hewitt said.

With AAP