NEW YORK — If it's true, as they say, that the toughest Grand Slam title to win is your first, then Andy Murray was right to feel relief, above all, when he finally got No. 1 out of the way at the US Open. “I certainly was doubting myself a bit, and thinking about the match and how tough it was going to be, and whether I was going to be able to do it or not,” Murray said Tuesday, a day after beating defending champion Novak Djokovic over nearly five hours in the final at Flushing Meadows, “so I'm just glad that I finally managed to do it.” As he spoke those words, Murray stared at his reflection in the shiny silver trophy he so longed for and now had earned, adding: “And I hope it's not the only one.” No reason to believe it will be. Indeed, with his defensive and returning skills, and a new willingness to be aggressive with his forehand, Murray might very well be considered the man to beat when tennis returns to the Grand Slam scene at the Australian Open in January. For proof, Murray needs look no further than his coach, Ivan Lendl. Until letting a two-set lead against Djokovic evaporate, then mustering all the gumption required to prevail in a fifth, Murray was winless in four previous Grand Slam finals. Only one other man in the history of professional tennis, which dates to 1968, lost his first four major titles matches. That man, of course, was Lendl, who eventually worked out how to win the big one and accumulated eight Grand Slam trophies of his own. Before Monday's match, Murray and Lendl chatted. Murray was anxious during his warmup in Arthur Ashe Stadium. He was anxious in the changing room. “He just said to me, when we spoke, ‘Just enjoy the match. It's what you work all your life towards, so just enjoy it,'” Murray said. “And I was like, ‘Well, that's exactly the problem. I've been working 10 years for this, and it's a big moment for me, so I don't know if I'm going to enjoy it.' And then he was like, ‘Oh, why not? You've got to try and enjoy it.' That was kind of how it went.” Murray clearly recognizes — how could he not? — and embraces the significance of his success in Britain, which last could proudly hail a male Grand Slam tennis champion in 1936, when Fred Perry won Wimbledon and the US Championships. It's been a summer of barrier-breaking by Murray, who was the first British man since Bunny Austin in 1938 to even be the runner-up at the All England Club (losing to Roger Federer), then won the singles gold medal at the London Olympics (beating Federer). “Winning a Grand Slam's been his goal and his dream since he was a very young kid playing tennis. And he's come so close a number of times and not quite made it,” said Murray's mother, Judy, who was Britain's Fed Cup captain. “I think winning the Olympic gold gave him the belief that he could do it in a major final. And to see him manage to do it yesterday, after such a tough, brutal match against a great player like Djokovic, was just fantastic. ... Hopefully, it will spur him on to more.” This has not been the easiest era to come along in men's tennis, of course. Federer owns a record 17 Grand Slam titles, Rafael Nadal owns 11, and Djokovic five. Those three guys combined to win 29 of the 30 major tournaments preceding this US Open (Juan Martin del Potro's 2009 victory in New York was the lone exception). But now here comes Murray, long considered by his peers a sure-thing, champion-to-be who just hadn't managed to decipher it all yet. Perhaps now he has. “Andy has been maturing very nicely as a player, as a competitor, as a person,” Lendl said. “As you mature, you become more comfortable in these situations. Of course, being in more of these situations, it's very important, and the more of them you're in, the more comfortable you feel.” Lendl speaks from experience. Murray said he won't know for sure exactly what sort of confidence boost he'll gain from these 15 days at the US Open — and one particularly engaging victory against a gritty competitor in Djokovic — until the next time he finds himself on court with so much at stake. He is certain, though, that he can't wait to find out. “I want to keep improving. I want to keep trying to win. ... I know, obviously, how good it feels to win a Grand Slam and, obviously, winning the Olympics. I know how hard it was, obviously, losing a Wimbledon final,” Murray said on Day 1 of life as a major champion. “You want to try to win those big matches in the big tournaments, and I'll keep working hard to try and do it again.” — AP