WIMBLEDON, England—The last time I saw Bernard Tomic was on Thursday in Eastbourne. He had just lost a late-afternoon quarterfinal to Gilles Simon, but he still wanted to hit some tennis balls. Or at least his father, John, wanted him to hit some tennis balls. A few minutes after Bernard’s match was over, the two of them, joined by a trainer and a hitting partner, were back out on a practice court. As the sun set and the last spectators strolled out, Bernard was still smacking balls at top speed, and his father was still urging him on from the sideline.

Father and son—as well as coach and son—were reunited on a tennis court. A month earlier, John had been charged in Madrid for head-butting a different practice partner of Bernard’s, Thomas Drouet of France, and subsequently banned from ATP events as a coach. The tour left it up to its individual tournaments to decide whether to sell John a ticket, or otherwise allow him on their grounds. Queen’s Club and Eastbourne let him enter the gates; Wimbledon didn’t. At Eastbourne, John was in his son’s corner quite literally, standing a few feet away from him on that tournament’s tiny side courts.

Today at Wimbledon, Bernard had to go it alone, and he wasn’t happy about it.

“It’s sad,” T0mic said of his father's forced absence from the All England Club. “It’s a shame because, you know, to have this huge tournament here and you’re competing, all of a sudden not to have someone there who’s been there your whole life is very difficult. It’s not a good feeling.”

Tomic blamed the ATP, rather than Wimbledon, for the situation. He claimed that the tour investigated the allegations against his father “on the telephone for 30 seconds" before it made its decision. "It’s very disappointing to have it happen like that,” Tomic said.

So much for the idea, at least for now, that Tomic might move on to a new, less volatile, perhaps more productive coaching set-up after his father’s arrest. While John has been a controversial figure for many years, the alleged assault shed new light on the complicated and at times star-crossed career of his son. We seemed to have a better understanding of why Bernard was prone to such drastic swings in motivation and on-court mood, and why he had yet to fulfill the promise he had shown as a world-beating junior. But it doesn’t look like there’s going to be any new coaching set-up. Bernard has always stood with his Croatian-born father in his battles with the national authorities at Tennis Australia, and he’s obviously standing with him in his battle against the ATP.

Even without his dad in the stands today, Tomic played a typically crafty match in pulling off a minor upset over 21st seed Sam Querrey, 7-6 (6), 7-6 (3), 3-6, 2-6, 6-3. What he lacked in aggressiveness and power, Tomic made up for with changes of speed, spin, and location. He says he needs his father, but Bernard can play thoughtful, resourceful tennis on his own when he’s in the mood. And while he has a habit of rushing when things go badly—“gritty competitor” is not how Tomic is typically described—he was clutch today. Tomic saved nine of 13 break points and five set points in the first set. He won 13 fewer points than Querrey, survived 36 aces and a bout of dizziness in the fourth set that required a visit from the doctor, yet still pulled it out in the fifth. He did that by saving his best for last. With Querrey serving at 3-4 in the fifth, Tomic hit three hair-raising winners to break.

It was a match of long lulls and easy holds; in my notebook, most games passed without a single comment. At one point, a man behind me asked his wife, with a gentle laugh, “You couldn’t possibly find two less effusive players, could you?” I was thinking the same thing: Other than very occasional growls of irritation at a missed shot or a close call, neither Tomic or Querrey showed a hint of emotion. That was true of their bodies as well as their faces. They moved from one point to the next with a detachment that bordered on the slouchy.

Querrey is a mellow giant from Southern California, but Tomic is something more confounding. He’s rebellious on the one hand, and he thrives on the home-court attention in Australia each January; he even said he got a boost from a few cries of “Ozzie, Ozzie, Ozzie!” that went up on Court 3 today. At the same time, he’s liable to go out and show a total lack of interest. The guy behind me today was right again when he said, of Tomic, “He just caresses the ball, he never really hits it.”

In some ways, that’s part of the plan; Tomic doesn't present a wall to his opponent, so much as a void. An unpredictable void. In one rally, he may go big with every forehand. In the next, when he’s given a short backhand to rip, he's just as likely to push it back into the middle of the court. Tomic has a magician’s hands, and can create shots that defy categorization. Yet he’s a magician who gets bored with his own act. In the end, he still relies too much on his opponents to make errors. Today Querrey, who went cold at all the wrong times, obliged. When Tomic does lean in and stick a ground stroke winner, you inevitably ask yourself, “Why doesn’t he do that more often?” He may still be caught wanting to play the game that made him so successful as a junior, and the more aggressive one he knows he needs to play as a pro.

For now the questions can wait; Tomic is moving on. A quarterfinalist here two years ago, he could do some damage again. He faces James Blake next, and is in Tomas Berdych’s fourth of the draw. Would Tomic be a better, happier, more mature player with another coach? Very few top male players end up being coached by a parent, and John Tomic doesn’t seem like he’ll stop being a figure of controversy and perhaps distraction—last year Bernard tried to have him removed from a court where he was playing. Yet the son, even with the father hovering, can obviously think for himself out there.

Last week the two were united on that practice court in Eastbourne. John Tomic clapped his hands and drove his son on, despite the fact that Bernard had just played a match. Even the pros who aren’t ultimately coached by a parent often owe their careers to the early vision and demanding will of their mother or father. John Tomic has most likely crossed the line, badly, in that role, but his son was still here today defending him as fiercely as possible.

In Eastbourne, as I watched them hit from a distance, John’s son laughed and shouted and took big cuts at his forehand; he was nothing like the blank-faced Bernard we see during matches. It looked, from where I stood, like he was having fun.