And now to rule the world: what would it take for Andy Murray to make world No 1?

Ask most players about future targets in terms of their world ranking and you'll get a short reply. They'll say it's more important to focus on the next tournament or even the next match rather than worry about the number alongside their name. "The world ranking will look after itself" is the mantra, almost as if talking about such matters would be as uncool as taking public transport back to the hotel.

Even Andy Murray, questioned in the wake of the Miami Masters triumph that ensured he would replace Roger Federer at No 2 in yesterday's world rankings list, said that moving up was important "purely because I was getting asked about it quite a lot" and he would not have to think about it in the weeks ahead.

From now on, however, you sense that Murray might take a much closer look at the weekly updates. Novak Djokovic, his long-time friend and rival, currently has a healthy lead at the top of the rankings, but the next five months offer Murray a chance of overhauling him. With only a modest number of points to defend during the upcoming clay-court season in particular, this could be the best opportunity Murray will ever have of joining the elite group of 25 men who have topped the world order. Moving up one place in the rankings might not be a big deal on most occasions, but it is when it means you are recognised as the best player on the planet.

"For me it doesn't change a huge amount, but the fact that I'm moving up the rankings is a good sign," Murray said on becoming world No 2 for the second time. "I've been winning a lot of matches. My consistency has been better over the last few months. The rankings obviously reflect that, so I will try and keep working hard during the clay and, hopefully, I can go higher."

It was immediately after Murray achieved his greatest ambition by winning a Grand Slam title at last year's US Open that he revealed how much becoming world No 1 would also mean to him. "For all players, once you get near to the top of the game, one of the goals is to try and get to world No 1," Murray said in New York last summer. "I'm definitely going to try. It's something I'd love to do."

Murray got to No 2 four years ago but stayed there for only four weeks. This time he looks sure to hold on for much longer. Indeed, unless there are injuries or major swings in form, the top five ranking positions (which are based on a rolling total of points earned over the previous 12 months and are updated after each tournament) are unlikely to change through the upcoming clay-court season or even before Wimbledon.

Although Murray can close the gap on Djokovic over the next few weeks, the world No 1 has a big lead. Murray, meanwhile, should stay clear of Federer, who is in the middle of a seven-week break which will end at next month's Madrid Masters. Having won in Madrid in 2012, Federer cannot improve his ranking points total until the Rome Masters and French Open – and would need to reach the final at least at both events to better his performances there last year.

Rafael Nadal, who was replaced at No 4 yesterday by his fellow Spaniard David Ferrer, also has his work cut out just to stay at No 5, given that he will need to defend successfully his clay-court titles at Monte Carlo, Barcelona, Rome and Roland Garros in the coming weeks just to hold his ground.

Sunday's Miami final signalled the end of the spring hard-court season and after this weekend's Davis Cup ties the focus will shift to clay. Although this is Murray's most challenging surface, he has plenty of chances to boost his rankings points total, especially at the French Open, where he lost in the quarter-finals last year. Djokovic, having reached the finals at Monte Carlo, Rome and Roland Garros in 2012, could easily lose some ground.

Nevertheless, if Murray is to become No 1 by the start of the US Open, where the Scot will be the defending champion, he may well have to win one of the next two Grand Slam tournaments, where the ranking points for the winners (2,000) are double those awarded for Masters Series victories. Murray's best chance is likely to be at Wimbledon, where he reached the final last year and returned the following month to win the Olympic gold medal.

With the rankings used to decide the seedings at tournaments, the main benefit for Murray of being No 2 will be that he cannot face Djokovic, the No 1, before the final in any event.

"Hopefully, it will lead to potentially advantageous seedings at the French and Wimbledon," Ivan Lendl, Murray's coach, told the BBC last week. "The draw will be really important. If Andy can get to No 2 and be seeded second, have a relatively freer path and the others play among themselves and take their physical and mental energy from each other, then the chances improve, providing Andy can do his job and beat the others."

While the current rankings mean that Murray could reach tournament finals without having to face any of the rest of the Fab Four, he knows that he might also have to beat all three of his main rivals to win a title: as No 2 there is a chance that he could face Nadal (No 5) in the quarter-finals, Federer (No 3) in the semi-finals and Djokovic (No 1) in the final.

Murray, however, prefers not to speculate on such matters. "I always say before the major events, and especially for me on the clay, there is no guarantee of me getting through any matches at the French Open," he said. "That's a surface I have struggled on in the past.

"But that's why the ranking system is there. You normally benefit from better draws the higher ranked you are. That's what the benefit is, whether it makes a difference at the French Open or wherever. You have to wait and see."

He added: "There's always upsets and stuff. Worrying about the quarter-finals or semi-finals of the French Open is pointless for me at this stage anyway. It's such a long way away. I'd rather focus on trying to win my matches."

And the world ranking will look after itself, he might as well have added.