Raonic is a dark horse for the title after backing up his run to the final at Queen’s three weeks ago by making the last four at the All England Club, his second major semi-final this year.
But Raonic, the son of engineers, who visits art galleries in his spare time, has been accused of being too passive on court, his clinical game perhaps needing an injection of flair and passion to upset the very best.
Enter McEnroe, whom the Canadian appointed to his coaching team ahead of the grass-court season with the aim of helping the world No 7 make the jump from challenger to champion.
Winning the crowd on Centre Court against Federer is, as Marin Cilic and even Andy Murray have found, an almost impossible task, but Raonic believes more aggression, both in his play and personality on court, can help destabilise opponents.
“First things John and I focused on when we were spending a week of training was really about not passing up any opportunities to come forward, to always keep the pressure on my opponents, keep them guessing, trying to make them play unbalanced as much as possible,” Raonic said.
“Then when we played the tournament at Queen’s, when I was playing, it shifted to putting those things in effect, but also about attitude on the court throughout matches.
“A big thing on his side was demeanour on the court, presence on the court. Both those things have been given quite a bit of attention too.
“He definitely keeps emphasising demeanour on court, which I probably would not have put in as one of the priorities for what I needed to improve at that moment.”
Raonic lost to Federer in straight sets at the same stage here two years ago, but the 25-year-old beat the Swiss in Brisbane in January at the Australian Open.