During my three years as a ballboy at the Miami Open I learned that, like a waiter at a Michelin-starred restaurant, we should be invisible unless summoned.

The players’ rage and adrenaline often smother the court, so when Fernando Verdasco snapped at a ballboy on court at the Shenzhen Open last week for being a millisecond late to deliver his towel, I was not surprised. I doubt the boy at the end of Verdasco’s anger was either: the job’s core is to tend to the players and umpire. The best ballpeople tether themselves to the wave and ride, although they still deserve respect.

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It’s not like the job doesn’t have its perks. We got free tickets and tennis gear, but the greatest prize was the privilege of being close enough to our idols to talk to them and – if you’re into sweaty athletes – smell them too. Between 2009 and 2011, I was lucky to be on court with every player – male and female – in the world top 25, except Rafael Nadal, Roger Federer and Juan Martin del Potro. Andy Murray could be grumpy but he was never abusive. Novak Djokovic and Gaël Monfils were fun and kind, but Marcos Baghdatis, who once told us jokes throughout a memorable doubles match, was my favorite.

Not everyone was as easy to deal with. Andy Roddick refused to pocket a ball or move a centimeter from his path to receive one. Your toss, with one bounce, had to land on his racket. Roddick wanted his towel after every point. And he played fast, so you had to pay full attention to his body language. On days when players like Nicolás Massú and Michaël Llodra, both notorious hotheads towards the end of their careers, were slated to be on court, the program director would call a meeting and warn us that if we were cursed at we should stay silent and still.

Beside discipline and fitness, the key strength for ballpeople is knowing the players’ superstitions. For example, although I was never on court with him, it was known that Nadal likes two water bottles, placed at his right foot. You were to hand them over for him to place. He always drinks the bottle on the left-hand side first, and places them delicately back in the same spot when he is finished. It’s been the same through his brilliant career. Upsetting his routine would likely end your chances of working in the big matches.

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The Miami Open made sure we were ready for the demands of the tournament. The program director boasted the Miami Open was second only to Wimbledon in the quality of its ballgirls and ballboys. Nearly 300 candidates tried out over the course of four Sundays before the tournament. The drills could be unorthodox: one measured how long we could keep our arms straight up in the air. We had to arrive at 7.30am sharp for the trials, and if you were late, you were instantly cut. During suicide sprints, the drill sergeant, an ex-military man, accused tired joggers of “hotdogging”, though no one knew what that meant. He would also make “boing boing” noises at heavier, slower runners.

Once you were in, it was great. You were a fundamental part of the tournament, with the best seat in the house – as long as you didn’t mind dodging 135mph aces from Ivo Karlovic. But we were always told we weren’t the main event, the players were – and we understood they would show flashes of temper. Releasing tension is necessary in a high-pressure environment, and on each point, their earnings were on the line. The job of the ballperson is to make it as easy as possible for players and they know that. But there’s a balance, and sportsmanship and respect are truest virtue of the sport. Verdasco should know that most ballpeople are either volunteers or making minimum wage – they’re really there for the love of the game.