Goran Ivanisevic has joined defending champion Novak Djokovic's coaching staff for Wimbledon.
The 2001 champion will work with the Serbian for the first week of the tournament at the All England Club, though he is trying to shuffle his diary to be able to stay longer.
Ivanisevic, the only man to win the singles title as a wild card entry, has previously coached Marin Cilic and Milos Raonic.
"A bit of a sudden call came a few days ago," the 47-year-old told Serbian news outlet sportklub.
"I was a little surprised, I travelled to Sweden, Nole wanted me to come earlier, but I had a senior tour event agreed. I came here this morning for the first training.
"Unfortunately, it seems that I will be able to be there only in the first week because I have obligations again.
"I'm trying to postpone them, although there are so many things.
"However, when Novak Djokovic is calling you, you put a lot of things on the side."
The best performances of big-serving Ivanisevic's career were on the grass, having been a beaten finalist three times during the 1990s before finally lifting the trophy in 2001.
Despite winning at Wimbledon four times, including last year, it remains the surface that Djokovic is least comfortable on, having never played on it until he had turned professional.
He said: "To be honest, I did struggle a little bit at the beginning, in the first couple of years of my career on the grass to really understand how I need to move on the court, how I need to adjust my swing and my game in general, tactically what I need to do.
"But over the years I guess you learn how to get used to it. Just have some form of a subconscious program from before that you try to unlock and remember and use it for the season every year."
Stan Wawrinka believes he can be a threat at Wimbledon this year, even though he admits finding grass challenging to play on.
The 34-year-old has won three grand slams, but has never gone past the quarter-finals at the All England Club, having made the last eight in 2014 and 2015.
He is yet to regain the heights that saw him clinch the French Open in 2015 and the US Open a year later following his knee surgery at the end of 2017.
But he feels he can spring a surprise this year.
"It has always been challenging for me on the grass court, for my game I like to have time, to have time to think a little bit more about what I want to do and to have time to get my confidence.
"I believe I am improving on this surface.
"I got some big results playing in the quarter-finals and if I can get through the first couple of rounds I can be dangerous."
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