Tim Clement, at the Australian Open, assesses the impact the 'super coaches' are likely to have on the men's game.
Our man at the Australian Open looks at the impact the 'super coaches' are having on the men's game as Andy Murray prepares to face Roger Federer
As if Andy Murray's clash with Roger Federer wasn't blockbuster enough, the Australian Open quarter-final clash contains a star-studded subplot with a first clash for the 'super coaches'.
Federer has turned to childhood hero Stefan Edberg in the hope of a similar impact to what Murray has enjoyed under Ivan Lendl, having gone from the nearly man of men's tennis to Olympic champion and two-time Grand Slam winner.
Novak Djokovic has also followed suit in appointing Boris Becker as his head coach, while the likes of Michael Chang and Goran Ivanisevic have also positioned themselves in the corners of current players.
However, the general feeling around Melbourne Park is that the impact of such appointments is being overplayed, especially for those relationships which have only been formed Down Under.
While a pat on the back from an idol is always going to be nice, what impact does it really have in the middle of a gruelling rally or when serving for the match?
Tactics look to be the main area of difference for Federer with Edberg, who is regarded as one of the best net players in the game's history, likely to help the Swiss star coming forward.
Impact
At 32, keeping pace with the top players from the baseline has proved increasingly tough, particularly against Murray and Rafael Nadal who both boast winning head-to-head records over the game's most decorated player.
Federer has also enlisted the help of a new racket, which boasts both more power and a bigger sweet spot, which sounds a no-brainer but has taken some adjusting to with some shock loses when initially rolled out last summer after Wimbledon.
However, an off-season's practice and the fresh inspiration of Edberg has brought better results this time round, with a first Grand Slam quarter-final appearance since the French Open.
The nature of his victory over Jo-Wilfried Tsonga will have particularly aided confidence, with more than twice as many winners than unforced errors and 34 out of 41 successful net approaches.
Whether Federer dares to be that brave against Murray will be interesting to see, with the Scot one of the best counter-punchers in the game with a particular relish for a target at the net.
I spoke to Murray after his third-round victory over Feliciano Lopez, who found it almost impossible to implement his own attacking game, and asked the Scot for his thoughts on the impact of the headline-grabbing appointments.
"I think it has been so soon that I you can't really say that the coaches will have been able to really implement any change," he said.
"I believe at this level it takes a few months of working with someone and working on specific things on a daily basis to really make a huge change, so I wouldn't have thought here you'd see a big difference or even a minor one.
"I think in a few months you'll start to see the work put in and whether it's worked or not."
The fourth seed is speaking from experience, having lost his fourth successive Grand Slam final here in 2012 while working with Lendl for the first time before going on to rewrite the British tennis history books.
Stability
One thing that really strikes you when covering a major is just how important the support networks are for players, with little other stability on offer during a year-long around-the-world tour.
It is no coincidence that the top players have the most consistent and well-structured set ups, with Nadal the perfect example with his entire career spent under the guidance of uncle Toni, while Djokovic won every title of his career with Marian Vajda.
The general assumption seems to be that Djokovic turned to Becker for a renewed inspiration after losing his world no.1 status to Nadal last year, but the Serb actually cited the change was due to Vajda wanting to spend more time with his family.
While the private lives of sports stars rarely warrants my attention, the fact that all of the 'big four' have been with the same partners throughout their careers reinforces the importance of stability.
In a sport where fortunes can change in an instance and delivering in the big moments is key, emotional calm is an invaluable asset.
Murray has found the right balance and I'd suggest that's to his advantage over Federer and Djokovic at Melbourne Park.
