Federer went on a rampage after getting that first break of serve, and was soon blasting winners all over the place.

“Come on Harris!” a fan in the stands shouted during the first-round match between Lloyd Harris and Roger Federer, and everyone who heard him let out a laugh. “You’re my hero, Lloyd!” the same fan yelled later in the match, and again there were chuckles all around.

We know why those seemingly innocent cries of encouragement inspired laughter. At Wimbledon’s iconic Centre Court, Federer’s first-round opponents don’t usually have many fans €” at least not vocal ones. Anyone making noise about that (typically unknown) name has got to be doing it ironically; Federer’s opponent getting loud, genuine support is just not supposed to happen.

What’s also not supposed to happen is Federer dropping the first set against that unknown player. As Harris took the opening frame 6-3, a hush fell across Centre Court. Who was this sluggish impostor, and what had he done with Federer?

The last time I had watched the Swiss from the stands, he was melting down (almost literally, given the intense New York humidity) against John Millman in one of the biggest upsets of all time. Naturally, visions of that stunner floated to my head in the second set on Tuesday; Harris was as much of a giant-killing candidate as Millman, and had the added advantage of being far more powerful and aggressive.

But I had forgotten that this was grass, where it only takes a point or two for the tide to turn. And at Wimbledon, there’s nobody better than Federer at turning the tide with a moment of €” genius? Inspiration? Inspired genius? It’s hard to put your finger on just how to describe the outrageous quick-court skills of the Swiss.

In the first set, it was Harris who pounced on that one decisive point. Federer had come out of the blocks looking sharp on his serve but a little off with his groundstrokes; he wasn’t exactly making errors by the truckload, but wasn’t being aggressive with his feet either. That gave Harris too much time on the ball, and he unloaded on a couple of forehands to steal a break at 3-2.

The young South African served out the set, but by the end of it, you could sense that Federer was starting to shake off the rust. The tide-turning change €” the ‘aha!’ moment, if you will €” came in the third game of the second set. Federer stood a step closer to the baseline for the return, hit a reflex volley winner that dropped dead after crossing the net, and followed it with a crisp on-the-rise backhand from inside the court. All of a sudden, he had three break points.

He needed all three of them, but everyone watching knew there would be no looking back from there. Sure enough, Federer went on a rampage after getting that first break of serve, and was soon blasting winners all over the place.

To make matters worse for Harris, he suffered an injury in the third set that affected his movement. You don’t want to be staring down the Wimbledon version of Federer while being anything less than 100 percent fit. Harris couldn’t muster much of a challenge in the fourth set; what seemed like a stressful match for Federer at the start turned into a regulation romp at the end.

Would it have turned out that way if not for Federer’s sneak move up in the second set? The final result would have probably been the same for any top player €” Harris was just too rough around the edges to win three sets €” but not all of them would’ve made it as comfortable as the Swiss. That Federer knew when to strike is down to his immense experience; that he could make it a no-contest after just that one strike, is down to his unique skills.

“With my experience, I stayed calm,” Federer said after the match. “I know I have other things in the bag that I can come up with, other tricks. I just took a bit of time.”

The ‘tricks’ that he talks of aren’t just the unbelievable drop shots or the sensational passing winners. They are also the little decisive steps he takes with his feet, the way he dances around the ball to position himself perfectly for the maximum-damage shot. That aggressive footwork was the most important trick he unfurled against Harris, and probably the most important reason he has won eight Wimbledon titles.

Federer’s instinct has always been to bound forward and use offence as a form of defence €” an instinct that reaps the richest rewards at SW19. When he advances menacingly up the court and the ball stays quick and low, his opponents aren’t left with a lot of options.

On grass, it’s not just one shot that can determine the result of a match; sometimes, it can even be one small step. As Harris discovered on Tuesday, and many others have over the last two decades, it’s almost impossible to push Federer back on Wimbledon’s grass once he has taken that decisive, game-changing step forward.

The Swiss might find it a little tougher to go on the charge in the coming rounds though €” not just because of the inevitable step up in the quality of his opponents, but also because of the prevailing conditions. “I just felt like it was slow,” Federer said. “I couldn’t really have any impact.”

He also explained how the ball being used for the Championships, coupled with London’s infamously damp weather, contribute to slowing things down. “I do believe, and I felt for years, that the ball is not a very lively ball. It’s more of a heavy ball. It doesn’t really go ‘whew’. Unless it’s really hot, then the ball goes a bit. (But) we are in England. It’s not like we have the superheat over here.

“I feel like it’s a bit of everything. I have to get used to it.”

How much of a factor will the speed of the court be over the course of this year’s tournament? It could possibly make a telling difference if the ‘Big 3’ reach the semi-finals and play against each other, where the margins are impossibly slim. But in the earlier rounds, Federer’s footwork will likely continue being the biggest factor.

If Federer is being aggressive with his feet, he will have little trouble countering the heavy ball or the cold weather or his opponents €” even if they are being (ironically or otherwise) cheered on by the fans.