Melbourne: Novak Djokovic and Roger Federer witnessed Andy Murray's drought-breaking successes after he hired Ivan Lendl as coach, and decided they were due for an overhaul of a major kind.
Both took on past Grand Slam champions ahead of the Australian Open, with Djokovic recruiting Boris Becker to help him try to win a fourth straight title in Melbourne and Federer working out a part-time deal with Stefan Edberg.
"It's great to see other legends of the sport coming back and trying to help the active tennis players during their careers," Djokovic said at Friday's draw.
Murray stuck with eight-time major winner Lendl, a partnership that has so far yielded titles at the US Open and Olympics in 2012 and at Wimbledon last year.
The No. 1-ranked players haven't yet followed the trend for celebrity coaches. Rafael Nadal tried some new therapies on his knees in the offseason but otherwise has an unchanged team led by his uncle Toni, who has guided his career since childhood. It was good enough to win him 10 titles last year and regain the No. 1 ranking after a seven-month absence from the tour.