(CNN) -- Keeping up with the changes in coaching personnel on the men's tennis tour can be difficult these days. Just ask Goran Ivanisevic.
"When I came into the locker room, I see the guys," explains the 2001 Wimbledon champion. "I thought I might be mistaken. Are we on the Champions Tour?!"
The Croat's tongue-in-cheek remark made at the start of the Australian Open serves to illustrate a novel situation where former grand slam winners are suddenly all the rage with today's top players.
Ivanisevic -- coach to compatriot Marin Cilic since 2010 -- and Ivan Lendl (who has been with Andy Murray since 2011) are old hands compared to the likes of Boris Becker and Stefan Edberg, who surprised everyone at the end of last year when they accepted roles with Novak Djokovic and Roger Federer respectively.
The German and the Swede met 35 times in the 1980s and 1990s, famously contesting three consecutive Wimbledon finals. Edberg won that particular battle 2-1 with both men finishing their careers with six grand slam titles. But how will they fair as coaches?
Pat Cash, a former rival of both and host of CNN's Open Court, admitted to "surprise and disbelief" when he got wind of Becker's appointment. He wasn't the only one.
"When Novak announced that Boris was going to be working with him I was honestly very surprised for a couple of reasons," two-time U.S. Open champion Tracy Austin told CNN.
"Novak had such a strong fall -- he was undefeated since the final of the U.S. Open where he lost to Rafael Nadal. He was 24-0 in the fall, so he was playing so well," she added.
"The other thing that came to mind was that I was surprised Boris wanted to do it. He seems to have such a full life with family and commentary. It's a big commitment to travel on tour with a player full-time. But it seems like Boris is really, really excited about doing it."
Excited and confident, judging by his comments prior to the Australian Open.
"I've been in 10 grand slam finals, I know exactly what a player feels like when he's in the later stages of a tournament," Becker told reporters.
"When you're 25 -- in my case -- I was better with a tennis racket and now I'm better with my mouth."
Djokovic has retained the services of long-time coach Marian Vajda, but will be hoping to learn from Becker's much feted skills at the net, Austin thinks.
It was here, after all, that the German made a name for himself during a 15-year career, winning thousands of points and millions of fans with his unique brand of athleticism and never-say-die attitude.
"(Djokovic) already has that from the baseline -- great defense, great offense -- but maybe he wants to round out his game a little bit more and be more forceful at the net, maybe have some better technique at the net," she says.
Retired doubles ace Mark Woodforde is more familiar than most with Djokovic's game. The Australian, who won 11 grand slam doubles titles with his partner Todd Woodbridge, coached the world No. 2 for a time in 2007.
"He likes to evolve his game and take advice from great tennis players and obviously he's gone for one of the all-time greats in Boris Becker," Woodforde said.
"I just wonder whether in the back of Novak's mind is the way Boris played -- trying to finish points a little more cleanly than what he's been doing in the past.
"Maybe he's trying to pick up on the style that Boris brought to the court himself -- the knowledge, the hustle bustle. You've got to think that the elongated points that he has to play these days, it's got to mount up."
Long points inevitably lead to long games, as Djokovic's fans in Melbourne are all too aware.
In 2012 he clinched his third title beating Rafael Nadal in a match lasting five hours 53 minutes -- the longest grand slam final ever -- and last year he took just over five hours to get past Stanislas Wawrinka in the fourth round.
However, the Serbian's three-year Australian Open reign came to an end against Wawrinka on Tuesday as the Swiss upset the odds to win a grueling four-hour clash and reach the semifinals.
While Djokovic tries to transition from baseline to net, Becker is plotting an entirely new path away from the commentary box.
The 46-year-old has reigned in his TV duties since accepting the coaching role, but his former Davis Cup coach Niki Pilic has urged Becker, whose private life since retiring in 1999 has been colorful and, at times, scandalous, to go a step further.
"There is no doubt he needs to change his lifestyle completely," Pilic said, Reuters reported.
"He needs strict discipline and a certain modesty. It won't be easy for him but he has no choice.
"He should not give too many interviews, must be restrained and do his work quietly. Above all, he must understand that he is not more important than the player. It will be an interesting experiment."
Can Ed help Fed?
Whereas Becker and Djokovic's partnership has caused a degree of head-scratching, the news that Federer had sought out the services of Edberg was much easier to understand.
"That one didn't surprise me," says Austin. "He looks up to Stefan. He was one of his idols. Roger, when he first came on tour, to me, would serve and volley and infrequently chip and charge, and now he doesn't do that as much.
Of course, that was Edberg's style of play, so maybe he's looking for that little extra element to elevate his game."
Edberg, now 48, has agreed to a part-time coaching role, spending 10 weeks with Federer this season, but is confident he can help the 32-year-old Swiss to an 18th grand slam title.
"He's such a great player, but there's always minor things you can work on," Edberg said recently. "That's why I do it, because I really think I can make a little difference. And if I can make a little difference, maybe that will take him back to where he was."
Woodforde is relishing the prospect of watching the partnership evolve.
"We all liked to watch Stefan Edberg play. It's almost when we watch Roger play now, everyone covets to see him. They always want him to win," Woodforde said.
"I'm looking forward to seeing how Federer profits from that. I think it's going to be so beneficial for him because that is probably that style is probably what Roger needs to move towards if he is going to have an elongated career."
With the business end of the year's first grand slam approaching, Federer will hope he can execute the strategies discussed with Edberg as he takes on Andy Murray -- his successor as Wimbledon champion last year -- in Wednesday's quarterfinals.
"The key thing for me is that this really shows how important these tiny little things can make," says Austin.
"These are all champions that we are talking about, they're already top players, but they are looking for any different margin to set themselves apart.
"In a match when they are playing against each other, it could be two or three points. It could be something that a former champion says -- the light bulb goes and maybe makes them feel more comfortable, more confident. If that makes the difference then it's all worth it."