If the tennis gods have their way, Rafael Nadal and Roger Federer will be stepping out for a semi-final showdown a week on Friday for their first ever battle at the U.S. Open.After 37 meetings all over the world, including in the final of each of the other three grand slams, a U.S. Open clash would complete the set.It is a contest Wimbledon champion Federer, who beat Nadal to win the Australian Open in January, would relish, having also beaten his longtime rival in Indian Wells and Miami this year.But Nadal, who regained the world number one ranking this month to be the top seed in New York, is focused on the bigger picture.“I prefer to play against another one,” Nadal told a news conference at Flushing Meadows on Saturday. “Is obvious, no? I am not that way. It sounds very good, but the real thing (is) I prefer to play against another player, an easier one if it’s possible.“I know you want to hear the other way - that I would love to play with him. No, of course I understand that it is going to be great for our history.READ | Roger Federer could face Rafael Nadal in US Open semi-finals“It is true that we played in all (the other) grand slam finals. We never played here and for sure this year we are not going to play in finals.“Meeting him here in the semi-finals, if that happens that will be something great and amazing, but as I say before, we made a lot (of history).”USA TodayRoger Federer will be looking to win his second Grand Slam title of the year after Wimbledon.Nadal is back as world number one for the first time since 2014, having won his 10th French Open title in June.A couple of underwhelming performances in the two Masters 1000 events this summer has not affected his confidence and he is hopeful of a third U.S. Open title, his first since 2013.“It’s good to be number one of the world again, of course,” he said. “I think it’s a good achievement after three years having some troubles. So, just happy for that.“For the moment I am very happy the way that I played during the whole season. I enjoyed almost every event that I played.”READ | Andy Murray withdraws from US Open due to hip injuryFederer, on the other hand, says he would love a big match against Nadal at the U.S. Open for the first time.“We never played here in New York so I think that would be fun for everybody involved,” he said. “But there are about 60 players between us who don’t want it.“I’d love to play Rafa here in New York. Hopefully it will be a night session. Hopefully that would be a great atmosphere and one again where we play great like at the Australian Open.”Nadal leads Federer 24-13 overall and 9-3 in grand slams but has lost their last four meetings.