If this French Open was the football World Cup (providing such a concept is not rendered beyond parody after recent events), Andy Murray, Novak Djokovic and Rafael Nadal would be in the group from hell. However, until they collide, all is going well enough for them, while Roger Federer, over in the group of serenity, is quietly doing his thing too.

On day five, there was little to disturb the tennis universe in the men’s draw, but interesting comparisons to be made as the favourites came through contrasting tests using their particular gifts.

Murray will be happy with the result, a little disappointed with a mid-match dip and encouraged that he could finish so emphatically to beat the eye-blazingly aggressive João Sousa 6-2, 4-6, 6-4, 6-1 in just over two and a half hours in his second consecutive appearance on Court Philippe Chatrier, normally Nadal’s unofficial pied-à-terre.

On the main court a little earlier, Nadal won his 68th match at Roland Garros, against a single, infamous loss, and is giving his critics something to think about after some low-key efforts on clay this summer.

After easing himself into the tournament he owns with a three-set win over the French teenager Quentin Halys on Tuesday, he went through the gears to dismiss his fellow Spaniard Nicolas Almagro for the 13th time in 14 matches on Thursday, this time 6-4, 6-3, 6-1. Nadal now seemingly has the easiest third-round challenge of the leading seeds, against the Russian world No120 Andrey Kuznetsov, who beat the 34-year-old Austrian Jürgen Melzer, a former world No8, 6-1, 5-7, 7-6 (7-0), 7-5.

However, Djokovic is still the tournament favourite. Although the world No1 had an injury time-out for attention to his lower back and groin on Court Suzanne Lenglen, he eased to a comfortable 6-1, 6-4, 6-4 win over Luxembourg’s Gilles Müller. Djokovic has yet to be properly tested but the young Australian Thanasi Kokkinakis – world No84 and a sometime training partner of Murray’s – might ask him some hard questions in the third round, having come through a stern test against his compatriot Bernard Tomic to win 3-6, 3-6, 6-3, 6-4, 8-6.

Murray next plays Kokkinakis’s more volatile countryman Nick Kyrgios, who is waiting for him without stress after Kyle Edmund withdrew from their match overnight with a stomach muscle injury.

After Murray’s win, the French former player Fabrice Santoro conducted the courtside interview dressed in a kilt. “Looks good,” the real Scot said, nonplussed. Murray added: “I realised towards the end of the second set and at the beginning of the third that he had raised his level. I just had to weather the storm, came up with some good serves on break points and managed to turn it around.”

Asked for the eleventeenth time about his French coach Amélie Mauresmo – who had slipped away from court but was caught on the big screen checking her mobile phone while waiting in the player’s corridor – Murray said: “She’s helped me a lot. She was an excellent player, played with a lot of variety, something that I tried to do on court. She’s a very nice person, which is important. So far, so good.”

That might have been an involuntary reference to the status of their relationship, as Mauresmo does not know yet how long or if her commitment to the job will last after she gives birth to her first child in August.

Sousa, who had not taken a set off Murray in five attempts, battled through seven deuce points on his opening serve over 13 minutes and still could not hold. Murray was at his relentless best, breaking then cruising to a one-set lead. But the Portuguese, with a smooth single-handed backhand and intelligent strategy, fought back hard – with a little help at a crucial moment in the second set.

The French chair umpire Pascal Maria interrupted Murray on his serve at 0-30 and 3-4, when he gave him a time warning that looked harsh with the Scot, a known quick player, having done no more than pause to settle when the wind gusted.

He lost the point and the game, and Sousa, playing at a far higher level than his world ranking of 44 would suggest, served for the set at 5-3. Murray showed his joy in retribution when he broke back immediately but had nobody to blame but himself when Sousa smashed a mis-hit winner to take the set on his next serve.

Sousa seized on Murray’s malfunctioning serve and, red-lining as if he were in the last moments of the final, turned the third set into a serious examination of his opponent’s resolve. He got another break point when Murray – having just reminded Maria he was not slow-serving but waiting for ballkids to reach their positions – looked distracted and his forehand went wide after clipping the net. He saved with his second ace of the match and won a marvellous, athletic point at the net.

Maria intervened again, however, as Murray was serving to hold and had to stall as the large video board was replaying the previous point. The player complained quietly about the ruling, took his punishment and made Sousa pay.

When he held to love and broke (during which he corrected the umpire in Sousa’s favour on a line call) for 4-3, Murray had regained the moral and athletic authority in the contest. He was rewarded for his patience, forcing an on-fire Sousa to the limits of his discipline in the ninth game, then, thankful for the return of his serving efficiency, held easily for a 2-1 lead.

Murray was reading Sousa’s game perfectly now. A set and a break down, Sousa still went for his shots, but fewer of them landed legally, and Murray’s run to the line in 24 minutes was untroubled.

Now for Kyrgios, a clash to savour.