Wake up, Manchester United fans! Jose Mourinho has still got everything to prove

Perhaps someone had forgotten to tell him.

Ricardo Carvalho, William Gallas, Paulo Ferreira, Joe Cole and Arjen Robben were all limbering up ahead of the League Cup third-round tie with West Ham. English football’s biggest distraction was being taken seriously – in October.

It worked. Chelsea arrived at the Millennium Stadium for the 2005 final with their primary objective on track: a six-point lead in the Premier League plus a game in hand. They departed the Welsh capital with the first honours of the Mourinho era, a triumph that was quickly forgotten when the first of two successive league crowns became the trophy cabinet headliner.

When Mourinho returned to Stamford Bridge after a six-year hiatus, he initially tiptoed around the League Cup.

But after settling in with a trophy-less season, he changed his tack and when a fifth-round trip to Derby appeared in December 2014, his medal-sense was whirring. John Terry, Cesc Fabregas and Eden Hazard were thrust into the starting XI, a move that risked derailing Chelsea’s Premier League bid with four festive fixtures crammed into 11 days on the horizon. It didn’t. They reached the final again, this time downing Tottenham 2-0 at Wembley before finishing the campaign as champions.

Mourinho grasped the power of momentum, using the League Cup – a comparatively simple trophy to win (Bradford and Cardiff City were finalists in 2012 and 2013) – as a springboard to greater honours.

It’s partly why, upon joining Manchester United, he elected to play a strong side against Manchester City in the fourth round, while Pep Guardiola rotated. It’s also why he insisted United were still unbeaten after a 2-1 defeat to Hull City, one that still saw them progress on aggregate, after a controversial penalty went against his side. "We didn't lose. It was only 1-1. I only saw two goals," he said afterwards. In his eyes, they were 18 games unbeaten.

It’s this refusal to accept defeat that makes Mourinho so revered; it’s also why his tenures end abruptly. He is consumed by his win-at-all-costs formula – a tactical approach that can’t fail if strictly adhered to, supposedly – so when it falls apart he simply can’t comprehend that he’s at fault. Instead of a confession he bleats betrayal. The end is inevitable.

His pursuit of substance over style doesn’t always please. When things go wrong, and he persists with his methods, it’s inevitable that cracks will appear in a squad so tuned towards winning. He may have survived the early condemnation at United, with the fans overly forgiving of their awful league position, but he is still teetering on a precipice of discontent. Lose against Southampton at Wembley Stadium and the rage machine will fire up again.

Why? The inconvenient truth is United have the most expensive squad ever assembled. Of course you’re going to win games – and play better football than David Moyes and Louis van Gaal – when you’ve had their summer influx. First was Eric Bailly, fresh from selection in La Liga’s Team of the Year, for £30m. Then came Zlatan Ibrahimovic, a four-time champion with Paris Saint-Germain. Henrikh Mkhitaryan, part of the formidable Borussia Dortmund axis with Marco Reus and Pierre-Emerick Aubameyang, soon followed for £26.3m. Finally, Paul Pogba, another four-time domestic champion, arrived for a world record £89m.

Throw in David De Gea, arguably the Premier League’s outstanding goalkeeper, and you have a spine capable of bulldozing the Premier League. Instead, Mourinho persisted with Wayne Rooney and Marouane Fellaini, while Mkhitaryan and Anthony Martial were culled. Pogba was not given the freedom his price tag deserved. Chelsea cemented the title by Christmas; United were squabbling over sixth.

After a horrendous wait, United fans are finally watching the team they want to see. There’s a collective relief that wins are coming easily again, with the standard of opposition conveniently ignored, and there’s a chance of immediate silverware.

But the jury should remain out on Mourinho. His changes mirror the wishlist of most supporters, while he is still the same man who steered Chelsea perilously close to the Championship. He'll just have to hope the League Cup, the catalyst for his success at Stamford Bridge, will spark a period of belated dominance at Old Trafford.