Virginia Wade admits she thought Andy Murray hiring Amelie Mauresmo was a joke and cannot see how the partnership can be a success.
Murray made the surprising decision to appoint former Australian Open and Wimbledon champion Mauresmo as his coach earlier this month, initially just for the grass-court season.
The Frenchwoman could hardly be more different in character to her hard taskmaster predecessor Ivan Lendl, who helped Murray cross the line to become a two-time grand slam champion and Olympic gold medallist.
The Scot will begin the defence of his Wimbledon title on Monday, the first British singles player to do so since Wade in 1978.
Wade told Press Association Sport: "There's not quite the same intensity about him as maybe a year ago. Having Lendl there really made him think, 'I've got him watching me so I better be absolutely full tilt all the time'.
"It's hard to read him. Mauresmo was a total shock, I thought they were all fooling around. I think again he's maybe trying to mess with everybody. I don't know.
"She was a great player, she's a great person. I think she was a little fragile mentally because she had the capabilities of beating everybody.
"She's laid back, she's a very nice, mature person. But I can't work it out at all. You like to try to get behind people's thinking but I can't really with this one. You try to see what somebody's going to offer that player.
"Unless he just needs somebody there to say 'well done', which is possible too. As a player you need somebody to endorse you sometimes and not try to change anything.
"I have to say I thought Lendl would be a difficult choice but that was very successful. In the end it's the individual who's playing who has to appreciate the input.
"Unfortunately as a coach your time does get dated because what you say gets a little bit repetitive after a while and the player needs a fresh input. I think basically he (Murray) dictates what he wants to do and the coach adds in between the lines."
Wimbledon was the last of Wade's three grand slam singles titles, coming when she was almost 32, and the defence of her crown ended in the last four.
She said: "I played a disappointing semi-final against Chris Evert. It was windy, not a very nice day, and I think in many ways I just bailed out, I wasn't prepared to dig deep to really try to win because I didn't believe I was going to. It can happen.
"The thrill is playing the opening match on Centre Court. It's a great tradition. Everything felt different after I won it."
Former British number one Greg Rusedski, who like Wade has been playing in the Liverpool Hope University International Tennis Tournament, believes Murray can go into the tournament with high hopes of winning back-to-back titles.
The Scot plays Belgium's David Goffin in round one and is in the same half of the draw as top seed Novak Djokovic, who he beat in last year's final.
Murray's excellent record on grass means he has been elevated in the seedings from his ranking of five to three.
"I think the seeding's worked out very well for him," said Rusedski. "Had he had to meet Djokovic, (Rafael) Nadal and (Roger) Federer back to back to back to defend the title, that's going to be difficult.
"I think he's in a good position and the pressure's kind of off him because he won Wimbledon, so he can go out there and enjoy it. And I think he will.
"He's achieved a lot of his goals: he's won Wimbledon, won the US Open, won an Olympic gold medal, and no one can ever take that away from him.
"Not many people get to go out there and open Centre Court, and if you do usually it's not because you're the defending champion, it's because you're playing the defending champion. Last year it kind of felt like it was his destiny."