Wednesday 6 July 2016 20:16, UK
Boris Becker, Ivan Lendl and John McEnroe have all joined the coaching staff of the cream of men's tennis - so what do they bring to the team?
Grand Slam winning coaches can provide invaluable advice to their proteges as they progress through the majors.
These superstar names have been in nerve-wracking situations, fought back from the near impossible and kept a level head to get themselves over the line and win the biggest prizes in tennis.
The relationship between coach and player is delicate; both will be highly driven and emotionally invested, and although this can lead to passionate success, the combination can also lead sparks to fly.
There are a variety of coaching styles throughout the men's game. The close-knit relationship between Novak Djokovic and Boris Becker is clear, as the German is an ever-present courtside. John McEnroe, who has been working with Milos Raonic, has to balance his coaching with television duties.
There are some players, such as Nick Kyrgios, who play without a coach to fit their unorthodox routines. Whatever the coaching schedule, when it comes to the latter stages of tournaments, the importance of having a proven champion in your corner cannot be understated.
Andy Murray won both his Grand Slams, as well as Olympic gold, under the tutelage of Lendl. On the court, Lendl won eight majors with a potent forehand laced with topspin. Although he missed out on success at Wimbledon (he made the final twice), he was a consistent champion, maintaining a 90% win rate in five different years.
Maintaining a low media profile, Lendl's steely resolve has been critical in developing Murray's character, channeling his frustration and refocusing when under pressure.
His reintroduction to Murray's team has added another dimension to the Briton's campaign and, following Novak Djokovic's exit, will be important in helping Murray manage the expectation of being overall favourite for Wimbledon 2016 as he takes on Jo-Wilfried Tsonga on Wednesday for a place in the semi-finals.
Raonic's five-set victory over David Goffin is the first time in his career that the Canadian has come back from two sets down to win - and it cannot be coincidence that it comes since the arrival of McEnroe to the team.
In the eight previous occasions Raonic has been down by two, he has lost all eight in straight sets.
Raonic benefits from a powerful serve, but his change to a more dictatorial style of play, an attempt to impose himself on the match, is an indication of the aggressive style that led McEnroe to seven Grand Slam victories.
Raonic's relationship with Moya is also new, having recruited the Spanish coach in January. After a promising Australian Open, where Raonic looked in good stead before succumbing to injury in the semi-final, the world number seven has continued to improve.
After reaching the final of the Aegon Championship at Queen's, Raonic has looked impressive at SW19. His fightback against Goffin showed a determination previously lacking in tough matches.
Having made it to the semi-finals at Wimbledon in 2014, Raonic will need to make the most of the advice given by McEnroe and Moya to beat Sam Querrey on Wednesday. Another big server, Querrey knocked out Djokovic, and will be hoping to capitalise on the opportunity.
Roger Federer highlighted the importance of neutralising the 'Ivanisevic factor' in Wednesday's quarter-final with Marin Cilic. Having worked with his compatriot since 2013, Ivanisevic was an influential part of the 2014 US Open campaign, in which Cilic beat Federer in straight sets on the way to claiming his only Grand Slam to date.
Cilic is aware of the advantage of having a major winner in his camp. Ivanisevic was triumphant at Wimbledon in 2001, and Cilic has talked of those experiences being crucial in his preparation.
"I think that's a huge help when you have something like that, especially someone like him who was Top 10 for many years in his career, and played many times in finals of Grand Slams."
Djokovic may have crashed out at Wimbledon, but six of his 12 slams have come in the time he has been working with Boris Becker.
Coming off the back of four final defeats in the previous seven Grand Slams, Djokovic hired Becker, a six-time major winner, in December 2013.
Success was not immediate, the Serb only reaching the quarter-finals in Australia in January 2014, but it was thereafter. Djokovic went on to make at least the semi-final of every slam until this year's Wimbledon.
Before the defeat to Sam Querrey and after his Melbourne exit, Djokovic reached eight of a possible nine finals in slams, winning six of them and becoming the dominant force in the men's game - and he is in no doubt of the German's influence.
"Boris Becker joining our team 12 months ago has brought a new fresh, I think, perspective of observation on my game," Djokovic said in 2015.
"He's contributing and sharing his advice on how he sees my mental approach to the big tournaments, big matches, and of course my game in general."
Wimbledon quarter-finalist Tomas Berdych split from Dani Vallverdu, a former member of Murray's coaching team after a 6-0 6-0 defeat at the Rome Masters, while world number five Stan Wawrinka turned to 1996 Wimbledon champion Richard Krajicek for the grass-court season and suffered early exits at both Queen's at the All-England Club.
So it doesn't always work - but when the greatest of them all feel seeking advice is worthy, then it is perhaps no surprise others have followed.
Roger Federer has never hidden from the fact he uses Stefan Edberg as a sounding board and the six-time Grand Slam-winning Swede was in his player's box earlier this week.
After 17 majors, including seven Wimbledon titles, the importance of Grand Slam coaching experience is not necessarily something Federer needs. Managing his fitness, particularly after recent injuries, is a more pressing concern.
Kei Nishikori is coached by Michael Chang, a Grand Slam winner at 17 and 2002 Australian Open Thomas Johansson is in the corner of world number 11 David Goffin, who is now competing regularly at the business end of tournaments.
Coaches? Mentors? Gurus? Whatever they are called, they are proving popular and perhaps most importantly, proving successful.
