US Open 2013: Roger Federer rediscovers his love for tennis after worst season in a decade Clearly when I had my two girls, I also wasn't sure right off the bat how it was going to be after that. Was I going to be able to play the same schedule? Was my love for the game as big? Were we going to be able to cope with the whole thing or not? (We) managed it totally fine. They were at the court today. I'm so happy to see them before and after the match. I'm in a good spot right now. I want to enjoy it as long as it lasts. The match had been scheduled for the night session on Monday but rain meant it was held over, and Federer, who next meets Argentina's Carlos Berlocq, was happy with how he handled the situation. He said: "There wasn't much rhythm out there, but I was happy the way I played overall. It's a first round after all. There was a bit of a breeze. I should have played at night; I played during the day. Overall I'm pleased to be in the next round. The tournament lost two of tennis' rising stars in the first round as Grigor Dimitrov and Jerzy Janowicz were sent packing. Dimitrov, the 25th seed, is yet to live up to his talent, with some standout victories accompanied by baffling losses. This fell into the latter category, with the 22-year-old Bulgarian going down 3-6, 6-3, 6-4, 5-7, 6-2 to world No 95 Joao Sousa. Janowicz's 6-4, 6-4, 6-2 defeat by Argentinian Maximo Gonzalez was even worse on paper but he was hampered by a back injury that took away the power of his fearsome serve. The 14th seed would have hoped to do damage here after reaching the semi-finals at Wimbledon and his exit along with that of Ernests Gulbis on day one makes a wide open third section of the draw even more so. Milos Raonic is also in that section and he must fancy his chances of going a long way. The Canadian 10th seed, who reached the Masters series final in Montreal earlier this month, beat Italian qualifier Thomas Fabbiano 6-3, 7-6 (8/6), 6-3. Asked if he feels he is ready to challenge at a grand slam, he said: "I think I can put myself in that position. I just have to make the opportunities and convert them. I think if I play well, I can get very close if not do it. It's still a long way to go, a very long way. Fifth seed Tomas Berdych, who took out Federer last year, could be a big threat in the tournament and he was an impressive 6-1, 6-4, 6-1 winner over Paolo Lorenzi of Italy. Thirteenth seed John Isner is the main American hope and he thrashed Filippo Volandri 6-0, 6-2, 6-3 - not too surprising considering the Italian has not won a Tour-level match on hard courts since 2008. Isner had been due to play on Arthur Ashe before Federer's match was rained off, but the American had no complaints. He said: "It was fine. I feel like I'm probably a better player on Grandstand than I am on Ashe, given that the court is smaller. There is not enough room to run around out there. It's not as windy. American qualifier Donald Young thrashed Martin Klizan, who beat Jo-Wilfried Tsonga here last year, for the loss of just two games while there were also wins for Gael Monfils, Tommy Haas and Sam Querrey but 15th seed Nicolas Almagro lost in four sets to Denis Istomin.