It is the sort of thing every parent tells their son before going out to play: make sure to have a proper breakfast. Unfortunately Bernard Tomic's father and coach John was not around to do so – he has been banned for allegedly attacking his son's training partner – and Tomic jnr did not think for himself. As a result he succumbed to dizziness and had to summon the doctor before recovering to knock out the No 21 seed Sam Querrey of the United States 7-6, 7-6, 3-6, 2-6, 6-3.
The youngest man left in the singles, aged 20, said afterwards: "I lost my energy and I think that was due to [the fact] I didn't eat as much in the morning. I only had a little bit of breakfast. It was a nightmare out there the third and fourth [sets]. I felt very dizzy. I was going to try to hang in there to see how I feel in the fifth set. That's when I got all my energy together and played all right. Somehow I won."
Victory did not assuage Tomic's anger with the Association of Tennis Professionals for not even allowing his father to attend Grand Slam events as a spectator.
"All of a sudden not to have someone there who's been there for your whole life is very difficult," he said. "It's not a good feeling. They investigated something on the telephone for 30 seconds and made a decision, which is very bad.
"Post-match we always get ATP people telling us what to say but I'm not going to say false things. I'm going to say the truth of how I feel. It's disappointing."
It can hardly have been the heat, even if temperatures had crept up a little to 18 C, but another man suffering was the 16th seed Philipp Kohlschreiber, who retired just as his match against Croatia's Ivan Dodig was approaching a climax.
He walked when trailing 6-4, 7-6, 6-7, 3-6, 1-2, citing tiredness and the after-effects of flu as Dodig began to overhaul him from two sets down. The German had been unhappy about a number of line calls as the match turned against him, but he said: "I was for the last three days almost entirely in bed. I felt like my body was really responding bad at the end and I had no energy left."
Grigor Dimitrov had earned himself a match on a show court by virtue of his status as a coming man and 29th seed rather than his role as the man in the so-called "love triangle" with rivals Serena Williams and Maria Sharapova.
Out on No 18 Court Sharapova's boyfriend and the man believed to be Williams's ex was far too good for Italy's Simone Bolleli, and was never close to dropping his serve in winning 6-1, 6-4, 6-3. Other than revealing that Sharapova had been unimpressed by his impersonation of her at the Boodles event last week, he declined to talk about personal matters.
Elsewhere David Ferrer, the fourth seed, dropped a set against Argentina's Martin Alund, a player ranked outside the top 100, but won 6-1, 4-6, 7-5, 6-2. Other top 10 seeds Thomas Berdych, Juan Martin del Potro and Richard Gasquet all came through too. Berdych beat Martin Klizan 6-3, 6-4, 6-4. Del Potro saw off Spain's Albert Ramos 6-2, 7-5, 6-1, while Gasquet defeated Marcel Granollers 6-7, 6-4, 7-5, 6-4.