The ice-cool Swiss barely raised an eyebrow as the male fan's cry thundered around a roof-covered Centre Court, and in four exhilarating sets he pricked, punctured and punched a mighty hole in champion Novak Djokovic's defences to reach a record eighth Wimbledon final.
For a man who had "missed being in the finals here the last couple years" and had been written off as a spent force by many critics, there were no over the top celebrations, deafening roars or fist pumps.
There was just a calm acceptance that he now stood three sets away from lifting a record-equalling seventh Challenge Cup, a feat which would draw him level with his hero Pete Sampras and William Renshaw.
"I'm aware that the tournament's not over yet. I didn't break down crying and fall to my knees (thinking) the tournament is over and I achieved everything I ever wanted," Federer said as he also eyes a record-extending 17th Grand Slam trophy.
"I'm very proud to have a shot of equalling Pete.
"Everybody knows what a hero he is to me and how much I admire what he's been able to achieve in tennis.
"I don't think he ever lost a Grand Slam final here at Wimbledon. He won seven out of seven, which is just incredible, particularly in the times he played against all these big servers (such as Goran Ivanisevic and Boris Becker).
"I admired how he stuck around, how he tried to win maybe one more, maybe two more."
Sticking around is what Federer has done well too since winning his last major at the Australian Open almost 30 months ago.
He has not let his barren spell get to him, always drawing inspiration from how close he has been to breaking up the Djokovic-Rafa Nadal duopoly that has swept the board in the last nine majors.
The Swiss came with one point of stopping Djokovic from reaching the 2010 US Open final, he came within two sets of winning the 2011 French Open crown and again held matchpoints against the Serb at Flushing Meadows in 2011.
Those near-misses kept the fires burning inside the Swiss even when, after contesting seven successive finals, he suddenly discovered that he had been struck off the Wimbledon guest list in the quarter-finals over the past two seasons.
"The first time when I didn't reach the final was a bit of a shock when I lost to Berdych (in 2010)," said the Swiss, who is bidding to become the first 30-something to win the men's title since Arthur Ashe in 1975.
"It was big news when I lost to Berdych. (Last year) I played so well in that quarter-final against (Jo-Wilfried) Tsonga it was a hard one to sort of accept to lose.
"Not that I started doubting myself after last year's quarter-finals, but ... you have to wait another year for your chance, and now I am finally back in that final. So it's great."
When Federer walks out for his 24th Grand Slam final, he will face an opponent who has never before experienced a second Sunday at Wimbledon.
If Andy Murray, and his 60-million followers, thought the Scot could rely on his 8-7 win-loss record to rattle Federer and end Britain's 76-year wait for a men's Grand Slam champion, the fourth seed might want to read between the lines.
The duo have met twice in Grand Slams, both in finals, and on each occasion Murray failed to win a set.
Federer is confident he can hold his nerves together for one final tilt.
"I wasn't nervous at all today before the match. I was almost a bit surprised I wasn't more nervous," said the Swiss, who will also equal Sampras's 286-week reign at the top of the rankings if he wins on Sunday.
"That means I'm in a good place mentally.
"There's a lot on the line for me. I'm not denying that. I've worked extremely hard since I lost that matchpoint against Novak last year at the US Open. Now I have a chance at world No. 1, at the title again all at once.
"So it's a big match for me and I hope I can keep my nerves. I'm sure I can."