The nature of the rescheduled French Open grand slam plays right into the hands of Novak Djokovic, according to Toni Nadal.
The uncle and former coach of 19-time major winner Rafael, says the colder temperatures in Paris and heavier balls are tailor-made to the Serbian World No.1's game.
Nadal is one of many players who has been critical of how the grand slam plays in autumn, compared to its usual slot around the European summer.
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Obviously the tournament had to be postponed because of the coronavirus pandemic that wreaked havoc on the sport earlier in the year.
As well as the new heavier balls, the overall playing conditions are radically different to when the tournament is traditionally held in May and June.
The temperature range for the tournament in Paris has been hovering between a chilly 10 and 15 degrees, with rain on most days making conditions particularly tough.
In a telephone interview from Mallorca, Toni told AFP that the radically altered conditions means the balance of power is tipped closer to the Serbian World No.1, who is chasing a second French Open title and and 18th major trophy overall.
Nadal, the 12-time champion, can equal Roger Federer's all-time mark of 20 majors with victory in the final.
However, the Spaniard's uncle says the 34-year-old’s task is more challenging than usual.
"Djokovic is very solid. I think he's the one who is most favoured by the new balls. It's more difficult for Rafael," said Toni.
Both Djokovic and Nadal have eased into the last eight in Paris for the 14th time and have yet to drop a set.
Djokovic has slipped just 25 games, Nadal two fewer as they remain on course for another championship clash.
Nadal's uncle went on to explain how the World No.2 has had to adjust this year at Roland Garros, as he chases a record-extending 13th title.
"I think Rafael has been quite good. He arrived with some uncertainties because this is the year he played the least before the tournament," added Toni of a truncated season due to the coronavirus.
Conditions causing a rethink for Nadal
Nadal skipped the US Open and his run to the quarter-finals in Rome last month was his first action since February.
"In the third round against Stefano Travaglia he played well. But Sunday against Sebastian Korda, it was too windy to really judge his game," explained Toni.
"As the conditions change, you have to impose your style of play. To win a point, you have to be prepared to play it longer.
"In previous editions, Rafael was very effective on points under rallies of nine shots.
"This year, the rallies are a bit longer. The topspin is not as effective."
Nadal next faces Italian 19-year-old Jannick Sinner who is the first player to reach the quarter-finals on debut since Nadal in 2005.
"He has everything to become one of the best players of the next generation. He is for sure a candidate for world No.1," said Toni Nadal.
"It will be difficult for Rafael, but he has the qualities to win.
"On Sunday, against Alexander Zverev, Sinner was on top the whole match. Zverev didn't play at a very high level, but Sinner is a very good player."
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