Rafael Nadal will reclaim the world number two spot in the ATP rankings from Daniil Medvedev should he win the Barcelona Open.
Nadal was surpassed by the Russian earlier this year after he was forced to pull out of Rotterdam and Acapulco due to injury.
However, he can ensure his stay outside of the top two can be a brief one by winning Barcelona.
He was a semi-finalist when the tournament was played last in 2019, losing to eventual winner Dominic Thiem. That means he can add 320 points to his current total with the title.
Medvedev, meanwhile, was a finalist in Barcelona last time, but he has been forced out of the tournament due to a positive coronavirus test at the Monte-Carlo Masters last week.
Current ATP rules mean players only lose half of their points if they miss tournaments during the COVID crisis, and the loss of those 150 points are enough to open the door for Nadal.
Any other potential movers?
Novak Djokovic is not playing in Barcelona, just as he didn't last time. The Serbian is on home clay instead in Belgrade, and he can extend his lead at the top of the rankings if he has a good tournament.
If both he and Nadal win their respective tournaments, though, his commanding lead will be cut by a tiny amount by virtue of Nadal playing an ATP500 and Djokovic an ATP250.
Arguably the form player in the ATP is Greek star Stefanos Tsitsipas. He won the Monte-Carlo Masters last week, but he can't make any further moves in the rankings if he backs that up with another title in Barcelona.
He can, though, close to within striking distance of Dominic Thiem in fourth position. Thiem won Barcelona last time, but has dropped 250 of those points as he misses out due to a knee injury this time.
Andrey Rublev, meanwhile, can break into the top six of the ATP rankings if he reaches the semi-finals in Barcelona. Alexander Zverev, who currently holds that position, is not in action.
A little further down the rankings, Denis Shapovalov could creep closer to the top ten if he goes deep in the tournament, while Jannik Sinner could make further inroads into the top 20.
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