A pumped-up Rafael Nadal qualified for the semi-finals of the Qatar Open on Thursday, battling to a three-set victory over Andrey Kuznetsov in the match of the tournament so far.

Nadal won 6-3, 5-7, 6-4 in just over two hours and was made to work for his victory by the Russian, ranked number 79 in the world, in a contest which delighted the centre court crowd in Doha.

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A relieved Nadal pumped his fist as he won, showing how much the victory meant to him.

“I am very happy to be through, he was playing great,” said Nadal immediately afterwards.

The Spaniard, looking to recapture the form that has made him a 14-time Grand Slam winner, won the first set comfortably enough but from there the real drama started.

Despite initially being a break up, Nadal lost a see-saw second set as Kuznetsov’s powerful forehands brought him back into the match.

The Russian eventually took it 7-5, the first time the 24-year-old had ever taken a set from Nadal.

In their only previous meeting, Nadal, 29, won in three sets at the French Open last year.

Then Kuznetsov won only six games on the Paris clay but on a hard court surface on Thursday he threatened to cause the biggest upset of the tournament so far.

The final set was also unpredictable, with number two seed Nadal again squandering a break advantage before decisively taking the Russian’s serve in the ninth game.

The world number five then served out immediately afterwards to secure a place in the last four where he will play rank outsider Illya Marchenko.

The Ukrainian continued his remarkable run, overcoming injury and France’s Jeremy Chardy to qualify for the semi-finals.

The world-ranked number 94, who knocked defending champion David Ferrer out in the first round, won in straight sets 6-3, 7-6 (7/3).

Chardy is ranked number 31 in the world.

Marchenko, 28, triumphed despite calling for two medical timeouts in the second set and receiving treatment on court from a physio for a back problem.

“My back didn’t work so well tonight,” said the Ukrainian. “I hope I am going to be better tomorrow.”

Marchenko also beat world number 50 Teymuraz Gabashvili in the second round.

Prior to beating Ferrer — the world number seven — in three sets on Monday, Marchenko had never beaten or taken a set from a top 10-ranked player.