SEPARATED at birth by but a solitary week, Andy Murray and Novak Djokovic have led parallel lives.

Both left home at a young age to pursue the dream of playing tennis at the top level and both achieved that goal. If the Scot has been to a degree in the Serb's shadow in recent years, Murray took a bold step forward with his victory over Djokovic in last season's US Open final.

Today, 15 years after their first meeting at an under-12 tournament in Tarbes in South-West France, where Murray won 6-0, 6-1, their stars collide again as Djokovic bids for his second Wimbledon title and his rival a first at his home Grand Slam. Including today's the two have contested three of the last four Grand Slam finals – Rafa Nadal's defeat of David Ferrer in Paris being the exception – and that is a pattern that looks set to continue, with Roger Federer's career perhaps finally on the wane and Nadal dogged by injury.

The encounter between the top two players in the world repre- sents the present and immediate future of men's tennis. The rivalry between Djokovic and Murray can now be regarded as the hottest in the game – meaning the tournament has served up a fitting pair of finalists on a day when temperatures are expected to hit 30C.

No wonder then that Murray feels his friendship with Djokovic has changed. "It's hard to say exactly," Murray said. "We have a professional friendship I think now. When we were younger it was more friendly. Now, you know, well, I still message him sometimes. We've spent a lot of time discussing various issues within tennis but I don't think it goes beyond that right now. I would hope when we finish playing it will be different. It's hard just now because when you are playing each other in big, big matches with a lot on the line, you can't be best of friends when that's happening."

It wasn't always thus. The similarities between the two are multiple, their shared interests and characters forging a bond at an early age, even if a teenage Djokovic struggled to understand the Scottish accent to the point where they had to converse via sign language. Both were born in May 1987, Murray entering the world first. They both have tennis-playing brothers, in Andy's case Jamie, a former mixed doubles champion at Wimbledon; in Novak's case Marko – in Glasgow this year to play in a Challenger event – and the teenage Djordje.

They both displayed sufficient promise and ambition. Murray left Dunblane for the Sanchez-Casal Academy in Barcelona at 15, and Djokovic started at Niki Pilic's academy in Munich when just 12. While Murray was winning the US Open boys' title, the best Djokovic could attain was a junior final place at the Australian Open.

Suddenly, though, it was the Serb who stole a march on the Scot. He was first to break into the world's top 100, then the top 10, and his first Masters Series win, in March 2007, came 17 months before the Scot would replicate that feat. With Federer and Nadal exerting a grip over the majors, the Serb was also first to reach his maiden Grand Slam final, the US Open in 2007, and the first to actually win one, the Australian Open in 2008 – he won his second against Murray in Melbourne in 2011.

The Scot, however, likes few things more than a target to aim at and Djokovic had the misfortune to become that man. Since that 2011 Australian Open final, their record in major finals stands at 1-1.

Now, the pair are so close, in terms of styles of play if not body shape, that the smallest thing could decide the outcome. They have met only once on grass, Murray winning in straight sets in last year's Olympic semi-final.

"We have played so many points, so many close sets, so many long rallies," Murray said. "I don't know exactly what it will be that will make the difference. But having played against him and won against him on grass will help me. I know what worked against him at the Olympics, and hopefully some of those things will work again. There are obviously some similarities [between our games] if you look at stats and stuff. I mean, both of us return well. That's probably the strongest part of our games. We both play predominantly from the baseline. We both move well, but with a different sort of movement.

"He's extremely flexible and slides into shots – even on the courts here. He's quite a bit lighter than me. So I'd say I probably move with more power and he's much more flexible than me. He never really has any letdowns physically, which he used to when he was younger. But sometimes it can depend on how the match starts. Sometimes one player can be extremely nervous beforehand."

Murray is determined to make sure that isn't him. He feels far calmer than 12 months ago, when he lost to Federer in the final, and hopes to be fresher mentally when he comes on court. Staying at home, and spending time with his dogs Rusty and Maggie reinforces that sense of normality.

Stress is also a given for his assorted watching family and friends, including girlfriend Kim Sears. "I have no idea whether it is tougher for her or me – she is the person you would need to ask," the Scot said. "It is a different sort of stress. Obviously she would like me to win but last year after the Wimbledon final she just wanted to make sure I was OK. But all I care about is winning."