Patrick Mouratoglou has experienced nothing but success since he started coaching Serena Williams last summer, but one thing is for sure - should the American's winning streak come to an end at Wimbledon, the Frenchman will definitely know about it.
This time last year the naysayers were once again writing Williams off and it was easy to see why.
The American had, after all, just crashed out of the French Open in the first round to then world number 111 Virginie Razzano.
The French Open was supposed to be the chance for Williams to re-establish herself following a testing and turbulent three-year period.
Williams was fined and disqualified for an expletive-laden tirade at a line judge at the US Open in 2009 and the following year she needed surgery on both of her feet after stepping on glass in a Munich restaurant.
So it was no surprise to see critics writing her epitaph when she lost to Razzano in a fiery-tempered match at Roland Garros.
Many decreed that Williams' love for the game was low as ever, that she needed to re-discover the drive and focus that helped her hold all four majors at the beginning of 2003.
She seems to have found new inspiration from Mouratoglou - the 43-year-old coach who has helped develop the careers of Laura Robson, Grigor Dimitrov and Marcos Baghdatis through his academy on the outskirts of the French capital.
Williams has won 73 matches and lost three since she started training at the Mouratoglou academy. Most importantly she has started winning majors again - three of them.
The latest victory came earlier this month when she beat her nearest rival Maria Sharapova 6-4 6-4 to win the French Open - her 16th grand slam.
The win put her two majors short of the 18 held by fellow Americans Martina Navratilova and Chris Evert and four shy of record holder Steffi Graf.
Mouratoglou thinks Williams is the only person who can prevent herself from reaching 18 majors.
He said: "She needs two more titles and, yes, I think she's going to get them.
"When she is in the right state of mind, she is unbeatable.
"She is a huge champion, what more can I say?
"It will only happen if her level of motivation goes down, and that is not the case today.
"Serena wanted to win the French Open at all costs. She found the resources, as she always does when she wants to win."
Speculation that Mouratoglou and Williams share a more personal relationship than one of coach and player has intensified in recent months.
The two have been pictured holding hands and sharing close embraces, but understandably neither of them will talk about it in public.
All relationships, regardless of their type, will have to endure rocky patches, and one will certainly come Mouratoglou's way should Williams fail to successfully defend her women's singles crown at SW19.
She explained: "If I lose, all hell breaks loose, literally.
"I go home, I practice harder, I don't like to lose. I hate losing more than I love winning. It could be a game of cards, I really don't like it.
"It happens in sport, you're going to lose. I learned that you're not going to win all of them and there have been a few matches that I wasn't disappointed in losing. It's actually helped me to get better.''
For a woman who is in the best form of her life at 31, that is a fearful message for Williams' rivals.
Mouratoglou has managed to make Williams something more than a juggernaut who is reliant on power.
She is a much more rounded player who is happy to hit delicate winners just as much as the ones that come from her trademark power serve.
So who has the mettle to stop Williams, who starts her latest Wimbledon challenge against Mandy Minella of Luxembourg, from lifting her sixth Venus Rosewater Dish on July 7?
Many see Sharapova as her closest rival, but Williams has beaten the Russian the last 13 times they have met.
After reaching the semi-finals for the last two years Victoria Azarenka is progressing well while Agnieszka Radwanska had the temerity to take a set off Williams in last year's final.
But there is a reason why Williams is the bookies' favourite to win next month, and if she does emerge victorious, her coach will be elated to have avoided the Serena hair-dryer treatment.