Madrid has been a Big Four stomping ground in recent years.

The Big Four—Roger Federer, Rafael Nadal, Novak Djokovic and Andy Murray—have combined to claim every Mutua Madrid Open title since Murray lifted the trophy in 2008.

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The last non Big Four Madrid champion was David Nalbandian, who made history in 2007 with a brilliant performance that saw him beat the world’s top three in succession—Nadal in the quarterfinals, Djokovic in the semifinals and Federer in the final—to take the title back when the tournament was staged on indoor hard courts.

Four-time Madrid champion Nadal carries a 10-0 clay-court, including collecting his 10th career titles in Monte Carlo and Barcelona, into next week’s Mutua Madrid Open.

Reigning champion Djokovic, who dethroned Murray to win his second Madrid title last May, said the tournament presents its challenges.

“People always talk about the dominance of the Big 4, I did not know we had won every edition of the Madrid event since 2009, that is pretty special for sure,” Djokovic told the Mutua Madrid Open website. “But I can say that it has not been easy for me the two times I won as I always had tough matches and great opponents.”

Though the draw has not yet been conducted, the tournament collaborated with artist Victor Jerez for these drawings of contenders.