Ukrainian tennis player Alexandr Dolgopolov claims that Rafael Nadal uses one main tactic which wins him 50% of his matches.

Nadal has had an amazing season, despite starting the year ninth in the world rankings.

He won two Grand Slams - Roland Garros and US Open - as well as titles in Beijing, Madrid, Barcelona, and Monte Carlo.

This incredible run, combined with the absence of many top players due to injuries, helped him finish the year as the World's No. 1.

The knee issues which Nadal had last year returned at the end of this season, however, and he was only able to play one match at the ATP Finals in London.

Alexandr Dolgopolov believes that the Spaniard has one main strength, but it is effective enough to win him most of his matches.

"Rafael Nadal's strengths are a frenzied spin and the fact that he is left-handed," Dolgopolov told Telegraf.com via Tennis World USA.

"Due to this rotation, he does not need to do anything else in half of the matches.

"He rotates to the left of the opponent and most players simply cannot cope, who do not have a very good left.

“Nadal won many matches due to one tactic – to play left with one hand."

However, Dolgopolov, ranked 38th in the ATP, believes Nadal`s awkward style is less effective on a faster surface. 

On grass, the ball has a lower bounce as the soil is softer than the materials used on the other types of tennis courts.

"On the grass with it (is) easier to play, its rotation does not have such an effect as on the ground or on the hard (court)."

Dolgopolov's words make sense when we look at the facts.

The Spaniard has only won one ATP trophy on grass for the last seven years - in 2015 in Stuttgart.

The Ukrainian holds a negative 7-2 record against Nadal, but he won their single match on grass - in London the same year. 

Speaking on his other victory against Rafa - an impressive 2-1 win on the hard court of Indian Wells, Dolgopolov explained: "On hard, when I celebrated the victory, I was just very confident, I was in shape, before that I had a great two tournaments and that's how it was."