Serbian Novak Djokovic survived his toughest test of the year so far as he battled through to the fourth round of the French Open ©Getty Images

Serbian Novak Djokovic survived the toughest test of the year so far as he battled through to the fourth round of the French Open with a four-set victory over 13th seed Roberto Bautista Agut of Spain at Roland Garros.

The 31-year-old, winner of the tournament on the iconic red clay in the French capital in 2016, booked his place in the last 16 with a 6-4, 6-7, 7-6, 6-2 win in a match which lasted 12 minutes shy of four hours.

Djokovic, seeded 20th as he continues his return from an elbow injury, was visibly angry in the second set, which he lost on a tie-break.

The 12-time Grand Slam champion smashed his racket into the ground on three occasions after he missed a simple forehand, drawing boos from the crowd.

It seemed to benefit the Serbian, however, as he returned for the third set with renewed vigour on his way to sealing victory in a gruelling encounter.

Spain's Fernando Verdasco awaits in the fourth round after he stunned Bulgarian fourth seed and Association of Tennis Professionals World Tour Finals champion Grigor Dmitrov with a 7-6, 6-2, 6-4 win.

Second seed Alexander Zverev also survived a scare as he saved match point in a five-set triumph against Bosnia's Damir Dzumhur.

Second seed Alexander Zverev also survived a scare as he saved match point in a five-set triumph against Bosnia's Damir Dzumhur ©Getty Images
Second seed Alexander Zverev also survived a scare as he saved match point in a five-set triumph against Bosnia's Damir Dzumhur ©Getty Images

Zverev, considered among a select few capable of dethroning defending champion and French Open king Rafael Nadal, had to do it the hard way as he was on the right side of a 6-2, 3-6, 4-6, 7-6, 7-5 scoreline.

"It was an amazing, high-level match," said Zverev.

"He served for the match and I had to save lots of break points in the fourth and fifth sets. 

"Sometimes you have to battle to get the win and that's what I did today."

In the women's singles draw, fourth seed Elina Svitolina of Ukraine crashed out as she was beaten 6-3, 7-5 by Romanian 31st seed Mihaela Buzărnescu.

Buzărnescu will next face 13th seed Madison Keys of the United States, who beat Japan's Naomi Osaka 6-1, 7-6.

Second seed Caroline Wozniacki of Denmark had no such troubles as she cruised into round four with a 6-0, 6-3 victory over Pauline Parmentier.