Paul Pogba entered the second season of his Manchester United return with a point to prove.Having been reunited with the Red Devils for a then world record fee of £89 million, the Frenchman embarked on a rather nondescript 2016-17 campaign. Flashes of talent were certainly there but the 24-year-old was far from justifying his weighty price tag.Nevertheless, he did end the season as he meant to start the next - scoring what essentially proved the winner in United's make-or-break Europa League final with Ajax.

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And Pogba, freshly liberated by the arrival of Nemanja Matic, showed his quality in the early weeks of the new campaign. The Frenchman has already collected an impressive two goals and two assists in just four league games.

Only Alvaro Morata and Henrikh Mkhitaryan have been involved in more Premier League goals so far this season.

As a result, United fans were justifiably worried when their star midfielder hobbled off the pitch during their Champions League victory over FC Basel. A hamstring injury was immediately suspected and current estimates suggest Pogba will miss the next six games.

Injuries are, of course, an unfortunate and recurring part of the game but there's more to Pogba's latest injury than previously thought.

Reports first emerged in The Sun that Jose Mourinho was livid about the injury once it emerged that the 24-year-old was undertaking extra work-outs with a personal trainer. As a result, Pogba had overworked himself, risking an injury that eventually struck against Basel.

Duncan Castles, of the Daily Record, has reiterated the report as well as revealing that Pogba was continuing to train this way against the club's wishes. Check out his tweet:

Contemporary footballers already face astronomical fitness standards but in this case, whether to improve his game, strength or other, Pogba has shot himself in the foot.

The news arrives in a month that has already seen Mourinho fall out with one of his midfielders, namely Ander Herrera. The Spaniard has made just one start in 2017-18, despite collecting the Sir Matt Busby Player of the Year Award last season.

It has emerged that the feud roots back to Herrera bringing a potential Celta Vigo insider to Carrington back in April.

Interestingly, though, Pogba's own dispute with Mourinho looks to be Herrera's ticket back into the first team. 

The moral of the story: don't mess with the Special One.

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