It might never have happened; he might have been the one that slipped through the net; Bayern Munich could have lost Mats Hummels. Now, they can't do without him.

It’s difficult to imagine the Bayern backline without Hummels. His calm aura and stylish, confident stride ball at feet, mixed with GPS-precise positioning and — when required — grit-sprinkled tackling have become a familiar, often insurmountable obstacle to Bayern's opponents.

"He's good on the ball, calm, plays without risks and has good vision," was legendary Bayern youth coach Hermann Gerland's verdict on Hummels. Not given to gushing, 'The Tiger', as Gerland is known, has overseen the rise of the likes of Philipp Lahm, Bastian Schweinsteiger, Thomas Müller and Toni Kroos to the first team.

Hummels has now joined them, albeit via Dortmund. And while Gerland's judgement remains true to this day, those were his thoughts on his then-teenage charge, who had barely made a name for himself outside of his own living room.

Given such high praise, it is a surprise that Hummels had to leave Bayern in order to flourish. Yes, Lahm went to Stuttgart and Kroos lifted spirits in Leverkusen before being whisked back to the Allianz Arena, but Hummels wasn't - at least not immediately. Bayern instead pinned their hopes on Holger Badstuber and — had Fate been more generous to the injury-ridden defender — they might have been right. Instead, the Bayern bosses were left almost like rueful fishermen: "You should have seen the one that got away."

"I was never called up to the national youth teams or the Bayern first team," noted a matter-of-fact Hummels shortly after moving to Dortmund in January 2008. "Others were always in it earlier than me. In that regard, I was also a late developer."

Hummels had gone to Bayern aged seven, a boy following his father, Hermann, who joined the club to coach the youth team. He returned in summer 2016, a €35 million footballer filled with experience and fine-tuned quality, honed over eight testing seasons at Dortmund that made him an established international and a FIFA World Cup winner.

Hummels chipped in with two goals for Germany as they were crowned 2014 FIFA World Cup champions.

It was an expensive return ticket, but one that Bayern surely cannot be regretting. Nonetheless, Hummels admitted they could not have been feeling that way when they let him go to Dortmund in 2007/08, first on loan and then permanently in exchange for €4 million 12 months later.

"I came out of the youth team, I could have still been playing for them," explained Hummels, who was just 19 when he moved to Die Schwarzgelben, allowed to leave despite the choppy waters being navigated by the first team at the time. "To have demanded something would have been out of the ordinary. My becoming a first-team regular wasn’t on the agenda."

How times change. Since his return, Hummels has played nearly as many league games as his three main centre-back partners — Jerome Boateng, Niklas Süle and Javi Martinez — put together. Like Gerland, who said he immediately had "100 per cent trust" in Hummels, Carlo Ancelotti has full confidence in his man.

Hummel helped Bayern finish with the Bundesliga's best defence last season, with only 22 goals conceded.

"Very important" for Bayern last season, according to the FCB boss himself, Hummels promises to be still more so this term with Boateng only just coming back from injury and Süle, the promising but raw summer arrival from Hoffenheim, on a pitiless, far-from-complete learning curve.

Hummels was himself a keen student who admits he had a "conflict" between pursuing a career in football and taking his school-leaving exams before Uli Hoeness convinced him his future was on the pitch, not in the classroom. The lessons he learned when thrown in at the deep end with Dortmund can now be passed on, helping not only Bayern's present but also their future.

"There is nothing better for a young player like me than to learn from the best," said Süle, who already possesses the welterweight physique of Boateng, but could still polish up his ball-playing skills alongside the unflappable Hummels, a master of the art.

At 28, and with his status reinforced by that success in Brazil and his standing in the Germany squad, Hummels has clearly adopted another role in the Bayern dressing room that Süle could also fill in the future: that of a leader.

With Lahm and Xabi Alonso both retiring at the end of last season, there weren't too many obvious candidates ready to not only face the music, but conduct the orchestra and point out the false notes. After 12 months bedding in as an old Bayern newboy, Hummels - who frequently captained BVB during his later seasons at the Signal Iduna Park - has decided he is ready to take up the baton.

"Too slow" and "complicated" was his withering critique of Bayern's laboured performance in victory at Bremen. "Football is about being clinical," he stated after defeat to Hoffenheim. It would have sounded like a cliche coming from many players. From the studied and thoughtful Hummels, it was a lesson in communication, a message to be heard and taken on board by the whole Bayern squad. It was one that was probably repeated in the Bayern inner sanctum.

Hummels is now at the heart of that, at the peak of his powers, having struck upon the Holy Grail of football: consistency. "I played a lot and consistently performed," he said after the 2016/17 campaign, where he was a pivotal figure in Bayern's fifth straight title win.

Watch: Bayern took Hummels' words to heart in their 4-0 dismissal of Mainz

He could have made the difference in other competitions too, but injury deprived Ancelotti of his talismanic defender for the tone-setting first leg of the UEFA Champions League surrender to Real Madrid - while the Italian substituted Hummels for Boateng with Bayern leading their DFB Cup semi-final against Borussia Dortmund 2-1. They lost 3-2.

"When I only take myself, my own performance and my standing, which I could still work on, it was a good year," Hummels said at the end of the last campaign. The current one could be his best yet.

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