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So even when she doesn't eat dog food the night before, Serena Williams finds playing her countrywoman Christina McHale to be a deeply unsettling experience.
Is Williams the greatest player in the history of the women's game? Until she puts herself level with Steffi Graf's modern-era record of 22 Grand Slam titles, which she might still do this fortnight, that's still under discussion. But here's what is already settled - that tennis has never seen a finer escapologist than this 34-year-old from California.
Certainly, there was no shortage of grass court jeopardy for Williams on Centre Court during this pulsating, second-round three-setter, with the defending champion and world No.1 dropping the opening set to McHale, an opponent ranked world No.65 and ninth in the United States. She also found herself a break down in the third set.
Some angst and drama had been expected from Williams during her trip to south-west London. Also scheduled at some stage in The Championships were those great stentorian cries that carry up the hill, past St Mary's Church and rattle the tea cups in Wimbledon Village.
What wasn't expected was that they would come in a match against McHale, in a match that lasted a minute under two and a half hours. To win, Williams had to go into "warrior-mode".
"Mentally, no one can break me," Williams said after her 6-7(7), 6-2, 6-4 victory, so swerving what would have been one of the greatest upsets in the history of the All England Club, or indeed the entire tennis map.
It was on the eve of a match at the clay court tournament in Rome in May that Williams had a spoonful of a rice and salmon dish that was supposed to be for her dog, Chip. It tasted "weird, like house cleaner" and Williams thought she was about to pass out. She didn't, and she beat McHale.
You have to imagine that Williams didn't make the same mistake again the evening before this match. Even so, this was a match that fried Williams' nerves, as well as those who wish her well. You had to pity Williams' mother, Oracene, who came to Centre Court for the end of this match, having just seen her other daughter, Venus, win a 10-8 third set elsewhere in the grounds.
The standing ovation that followed this match was for Williams, but also for McHale, who refused to be intimidated and played some spirited tennis. This was an occasion that sent Centre Court into overdrive, and had Williams bashing her racket on the grass, for which she picked up a code violation (that was shortly after the Hawk-Eye computer had made a decisive intervention when she had a point for the first set).
For the past year, Williams has been 'stuck' on 21 Grand Slam titles. Of course, there are worse places to be stuck (try zero), but the last 12 months haven't been an enjoyable ride for Williams.
After losing to Italy's Roberta Vinci in the semi-finals of last season's US Open, she was beaten by Germany's Angelique Kerber in this year's Australian Open final, and by Spain's Garbine Muguruza in Roland Garros. A day after Muguruza departed this tournament, Williams was in danger of being bumped from the draw.
Still, recall how Williams came so close to defeat in the first week of last summer's Wimbledon - she was two points from losing to Britain's Heather Watson in the third round - and yet went on to win the Venus Rosewater Dish. Next for Williams this fortnight is Annika Beck of Germany.
Much of the opening set was played with the roof open and under darkening skies, with the court so gloomy that the numbers on the scoreboard were glowing. Rain was on its way.
On the resumption, and with the roof now closed, McHale kept coming for Williams. Even so, Williams came within a point of winning the first set. In fact, she came within a pixel or two.
It was when McHale was serving at 4-5, 30-40 that Williams had her opportunity and it appeared as though the set was hers when the unseeded player's forehand was called 'out'. McHale challenged, and the replay determined that the ball had touched the back of the baseline.
On losing the tiebreak 9-7, Williams returned to her chair and smashed a racket on the grass. She then tossed it behind her, where it was caught by a television cameraman. "I was really, really angry in that moment," said Williams, who after the match passed the racket to a fan waiting by the exit.
There was a let-up from McHale in the second set, which passed quickly. How she came back in the decider. She was the one who broke first. But she didn't help herself in the next game by throwing in some double-faults, and Williams had parity. At the close, Williams' talents as an escapologist came to the fore and she broke again to take a 5-4 lead before serving it out. Warrior-mode Williams was through.
