'Unacceptable' - Tiafoe apologises for umpire tirade

American player Frances Tiafoe has apologised for a furious outburst in which he repeatedly swore at the chair umpire following his defeat in the Shanghai Masters.

Tiafoe, 26, reacted angrily towards chair umpire Jimmy Pinoargote after losing 5-7 7-5 7-6 (7-5) to Russia's Roman Safiullin.

Tiafoe could face a fine of up to $60,000 (£46,000) with the tirade classified as a verbal abuse offence under ATP rules.

"I really apologise for the way I acted," the world number 17 wrote on Instagram.

"That is not who I am and not how I want to treat people."

Tiafoe's outburst came at the end of a match that turned on the American being given a time violation at 5-5 in the tie-break.

The two-time US Open semi-finalist claimed he tossed the ball up to serve, but Pinoargote disagreed it was a legitimate throw intended to start the point and penalised him.

Forced to start with a second serve, Tiafoe lost the point after an exciting all-court exchange for 6-5 to Safiullin, who clinched victory at the first attempt.

As Tiafoe walked towards the umpire's chair, he launched a flurry of expletives at Pinoargote in a prolonged outburst.

"I let my frustration in the heat of the moment get the best of me and I'm extremely disappointed with how I handled the situation," Tiafoe added.

"That's not acceptable behaviour and I want to apologise to the umpire, the tournament and the fans."

The incident may be escalated if tournament officials feel it was 'flagrant and particularly injurious to the success of a tournament, or singularly egregious'.

If Tiafoe's actions are considered an 'offence of aggravated behaviour' or 'conduct contrary to the integrity of the game', he could face a larger fine.

Classy Djokovic continues pursuit for 100th title

Novak Djokovic continued his pursuit of a 100th career title by dismantling Italian youngster Flavio Cobolli to reach the last 16 in Shanghai.

The 37-year-old Serb was sharp and clinical in a 6-1 6-2 win, which took little over an hour.

Cobolli, who grew up idolising the 24-time Grand Slam champion, could not cope with Djokovic's ability to anticipate the rallies and rarely miss a return.

As well as his unerring precision with clean groundstrokes from the baseline, Djokovic's high level ensured he conceded only seven points on serve.

Next, the world number four will face Russian Roman Safiullin for a place in the quarter-finals.

Djokovic, on 99 titles for now, is aiming to become only the third man - after Jimmy Connors (109) and Roger Federer (103) - to clock up a century of tournament victories.

Making his first return to Shanghai since 2019, Djokovic acknowledged the prospect of winning a landmark title is giving him "extra motivation" in the ATP 1,000 event.

Novak Djokovic is a record four-time champion in Shanghai

Djokovic has scaled back his schedule as he prioritises the biggest events and this year has played his second-fewest number of matches in a single season since 2005.

The manner in which he overwhelmed 22-year-old Cobolli, ranked 30th after a impressive breakthrough season, was a reminder of the threat he poses.

"I was pretty sharp," said Djokovic.

"From the beginning, I had a clear gameplan of what I needed to do, staying aggressive and use every short ball to take initiative in the point. I've done that.

"I'm very glad for the performance."

Meanwhile, German second seed Alexander Zverev took his eighth match point to beat Dutchman Tallon Griekspoor, while other top-10 seeds Taylor Fritz, Grigor Dimitrov and Stefanos Tsitsipas also progressed on Tuesday.

Tsitsipas beat France's Alexandre Muller to set up a fourth-round meeting with Russian fifth seed Daniil Medvedev, relaunching a rivalry that has provided drama in the past.