For the last decade, the most interesting narrative in men’s tennis has been the race to hold the Grand Slam titles record. And for most of this story, there have been three main players: Roger Federer, Rafael Nadal and Novak Djokovic.

Federer dominated the mid-2000s, winning 11 titles in four years and giving himself a massive lead over the other two contenders. Nadal steadily reeled him in, winning 12 of the last 15 French Opens, where his prowess on clay has no match. And Djokovic, who started later and has had to make up ground, has shown dominance in recent years arguably more impressive than those of the other two in any stretch of time

The “Big Three” have won 56 of the last 67 Grand Slams. Now, with Federer at a total of 20 titles, Nadal at 19 and Djokovic at 17, this race is closer than it has ever been. The stage was set for the slams in 2020 to play a huge role in determining which of these legends will finish his career atop the pack.

Unfortunately, like almost all other professional sports, tennis has been put on hold for a few months because of the COVID-19 crisis. This necessary pause has major consequences for the game, as well as implications for the three star players and their quests to win the most slams.

The slams’ reactions to the pandemic vary according to when they were scheduled to occur. The Australian Open already took place in January, crowning Djokovic champion there for the eighth time. The French Open, which usually starts in late May, was postponed to Sept. 20, Wimbledon was canceled for the first time since World War II and the U.S. Open, which starts in late August, has made no changes to its schedule.

Depending on how you look at the situation, Federer’s career is impacted the most and the least by these changes. In late February, just a few weeks before tournaments started being canceled, the 38-year-old announced that he had undergone knee surgery and would be sitting out while recovering for the next few months. This means the time he is missing now is time he would have been missing anyway, and the French Open that he wasn’t going to be able to compete in is now back on the table.

The bad news is he’s unlikely to win the French Open as long as Nadal is healthy, and the tournament he would have had the best shot at winning, Wimbledon, is outright canceled. If Federer is to build on the lead he has over his competitors, he will likely have to make a stand at the U.S. Open, which he has not won since 2008.

As he is the oldest of the Big Three, Federer’s window of opportunity is closing the fastest, but with a break from the action, it’s also possible he will return rejuvenated, like when he won the 2017 Australian Open after taking six months off from the tour.

The changes to the tour’s schedule are less detrimental to Nadal’s slam race, as his last 11 slam titles have come from the U.S. Open and the French Open, but they will still impact him. If he is to win the French Open and the U.S. Open, as he did in two of the last three years, he will have to lift the trophy at the hard courts in New York and then immediately rework his game to suit the clay courts of the French Open, which starts just one week later.

Nadal is a man of meticulous routine, known for obsessive attention to detail down to the perfect alignment of his energy drink courtside. This improvised schedule could throw him off just enough to make a usually inevitable French Open win a little harder to reach.

Djokovic, on the other hand, is affected very minimally by the changes to the schedule. He won Wimbledon the last two years, so its cancellation takes one winnable slam away from him, but his efforts to overtake Nadal and Federer are otherwise unaltered. For him, it has always been about outlasting their primes, and he’ll get plenty of chances to make up the three-slam deficit he currently faces at the upcoming tournaments on hard courts and grass courts.

The race among these three players is so precariously balanced right now that there’s really no telling who will end up on top. Eventually, the next generation, aided by youth, will surpass the three greats, but when that will happen is anybody’s guess. For now, the Big Three have won the last 13 straight slams, appearing as strong as ever and motivated by the greatest race tennis has ever seen.