His expressive, tenacious playing style has often seemed at odds with the approach favoured by José Mourinho.
The sense of unease has not been helped by Sánchez, who doesn’t always do a good job of hiding his exasperation.
Perhaps, though, it is justified. Sánchez has been repeatedly criticised for what many consider below par performances this season, and on the surface, it is easy to see how that conclusion has been drawn.
He has, in nine Premier League appearances, scored just once and provided two assists. He has only started in five of those games. And he does not appear to be the same player who performed so consistently in north London. Reports have even surfaced suggesting that he won’t be at Old Trafford for much longer.
The stats, though, suggest that Sánchez may have been unfairly made a scapegoat. He has, despite the criticism and despite Mourinho’s apparent reluctance to start him regularly, been United’s most creative player this season.
The Chilean has created an average of 0.78 big chances per 90 minutes, a total bettered only by four other players in the division. He has also made, on average, 2.36 key passes from open play per game. And his xA per 90 is 0.29, by some way the highest of any United player.
That Sánchez’s teammates are not converting the chances he creates partly explains his almost constant state of exasperation. By comparison, Paul Pogba has created 0.26 big chances per 90, and Anthony Martial 0.31.
The 29-year-old, then, has certainly not been ineffective. If anything he has been unfortunate. Had he played more regularly this season the outlook might have been very different.
It was certainly strange that he did not start in United’s recent trip to rivals Manchester City. He has, in recent weeks, upped his performance levels, impressing in the Champions League victory away at Juventus and in wins against Newcastle and Bournemouth in the Premier League, in which he was deployed in his preferred central striking role.
There is evidence to suggest that United are a better team when Sánchez plays, too: they have won five and drawn two of the seven games he has started in all competitions.
Clearly, though, it is not enough. It may be that his attitude has alienated him from Mourinho and his teammates.
But he cannot be blamed for the team’s shortcomings when he is demonstrably their most potent creative force.