Throughout his recovery, that belief proved his salvation. In April, just as he was getting used to being outside, he endured three bouts of fever in quick succession. It set him back by a month, more or less, and was solved only when he decided to have his tonsils removed.

He had spoken earlier, vaguely, about perhaps playing on Manchester City’s preseason tour of the United States in July. That lost month ensured a return then was impossible. He would have to wait. That is the problem with targets, if you miss them.

It was in the final weeks, though, as he inched closer and closer to the field, that he saw the true value of the day-by-day approach. By August, Gundogan believed he was ready. He had returned to Manchester at the end of June after a three-week vacation — a house in Los Angeles with the seven, a few days in Las Vegas, a trip to Turkey to see his parents and grandparents. On the flight home, he said, he felt “relaxed, something inside me bubbling up, a new motivation, a new energy.”

At first, he was alone again — the bulk of Guardiola’s squad would not return from the summer break until July — but the solitude did not feel oppressive. When his teammates did come back, Gundogan would be following much the same program as them.

“It is brave to say it,” he said then, “but I feel as though my rehabilitation is over.”

Having gone through all that he had, those final few weeks — the finish line in sight — should have been torture. He not only had to watch as City added $300 million of talent in the transfer market, but he also had to cope with the loss of control, too.

Gundogan had always had a degree of agency over his recovery: he governed its pace, slowing down if he felt a twinge, speeding up if he felt ready. But now he was caught in that Catch 22 — he needed games to be truly ready, but he needed to be truly ready to get games — and he was at the mercy of Guardiola. Only he could know for certain when Gundogan would get the call.

City’s preseason tour came and went; Gundogan did not play. He was given a few minutes in a friendly game against Girona on Aug. 15, but by the end of the month, he had still not featured in a competitive match. He was named as a substitute in City’s first two games of September — at home to Liverpool in the Premier League, away at Feyenoord of Rotterdam in the Champions League — but was still only a spectator.