Behind the baby face, there lies an assassin.
Ole Gunnar Solskjaer is not the type to publicly malign a player or castigate them for a poor performance, unlike some who have previously sat in his chair.
But he is not afraid to admit and address problems either, and when he does, he does so in a tactful yet forthright manner.
With the scoreline still at 0-0 in stoppage time at the end of the first half, and with Jesse Lingard feeling the effects of a hamstring injury, Solskjaer turned to Sanchez.
In the 45 minutes which followed, Sanchez did not muster a shot, a dribble, a cross or particularly incisive pass.
As Thomas Tuchel’s visitors marched into a two-goal first-leg lead away from home, the Chilean was powerless to help United reduce the deficit.
In a year-long Old Trafford career of disjointed and inconsistent displays, it may rank as the most disappointing.
And not least because it came at such a rarefied level, one which players of Sanchez’s calibre are supposed to rise to.
In fact, his greatest contribution to the evening came before he was even introduced. While warming up down the touchline, shortly before coming on, he unknowingly clattered into the assistant referee, sending both himself and the official into the ground.
Solskjaer was later asked what he could do to help turn Sanchez’s Old Trafford career more sublime than ridiculous, but United’s caretaker manager was quick to point out that it is not his job.
“I’m not the one,” he said. “I can’t do anything about Alexis Sanchez. When he plays he needs to finds himself because we know there’s a quality player there.”
At this point, it would be unfair not to highlight the context which surrounds Sanchez and his struggles.
The Chilean was always sceptical about leaving London and his preference to live close to a large city ruled out a move to any Premier League club outside the capital or Manchester.
He has struggled, too, since the breakdown of his relationship with a former girlfriend last year and he found Jose Mourinho to be a difficult taskmaster.
Solskjaer, meanwhile, now has an established and relatively successful front three in the shape of Marcus Rashford, Anthony Martial and Lingard.
Short of gaining a yard of pace, shaving seven years off his birth certificate or waking up one morning with a Wythenshawe accent, it is hard to see how Sanchez forces his way in.
Some sympathisers might fairly argue that he cannot consistently impress until he is given consistent minutes.
But Sanchez is not a young talent adapting to a new country who needs to be nurtured and given greater opportunities to impress than those more deserving.
He is a 30-year-old who has spent the best part of five years in English football and arrived at Old Trafford promising immediate results.
Solskjaer’s sensitive yet pointed appraisal of the player’s performance on Tuesday night reflected that.
Sanchez would do well to heed the advice, lest he become one of the assassin’s next victims.
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