“He wants to play, he loves to play.” And so he does. For all the overblown shemozzle of Alexis Sánchez’s long goodbye from Arsenal, the dizzyingly tedious debates over net cost, balance of the deal, the artfully shot piano-plonking video cut, one thing has remained unaltered. Sánchez is a wonderfully pure footballer, a multimillionaire athlete who, as José Mourinho said before kick-off at Huish Park, really does just love to kick a ball around.

Sánchez was busy, full-blooded and in flashes quietly brilliant during his first hour as a Manchester United player. Before this FA Cup fourth- round match there had been the usual drooling rags v riches talk, a modern version of The Magic Of The Cup that tends, in this most materialist of ages, to focus on the finances, the Alexis-Sánchez-could-buy-the-whole-of-Somerset schtick.

Marcus Rashford douses Yeovil’s fire to see Manchester United easily through Read more

It is a part of football’s enduring strength that this stuff still melts away, that the world’s richest club against one struggling to stay in the league is still the same old game between the same human parts. On a cold, boisterous night Yeovil Town provided brusque and muscular opposition, a credit to the enduring strength of the Football League. Sánchez simply played the ball, the day, the game, setting up United’s first two goals, riding assorted heavy challenges and even handing some back in return.

Even watching United come out to warm up had provided a moment of gawping fascination. Before the game Mourinho had compared Sánchez to a prized juicy orange at the top of the tree. In this current United team he is more a baby clementine among the grapefruits, a centimetre shorter even than Juan Mata, who started here, fresh from addressing the reptilian illuminati overlords of the Davos World Economic Forum.

Instead Sánchez is all concentrated presence, the most imposingly power-packed footballing half-pint in the league. And as he waved to the crowd at the edge of the pitch something odd happened. Even in a magenta bib doing shuttle runs between some cones, he really does look like a Manchester United player.

Facebook Twitter Pinterest Alexis Sánchez warms up in Yeovil with his new team-mates. Photograph: Paul Childs/Action Images via Reuters

The Chilean started on the left of United’s attack, staying wide, braving the ire of the Screwfix Stand, which rang with one or two gentle pantomime boos. His first significant act was to pull the ball out of the air and nutmeg the nearest opponent. The away end roared. “You’ve dropped a tenner Alexis,” someone yelled. He did look rusty at times. With nine minutes gone Sánchez turned inside and punted a cross-field pass that was easily intercepted. And he did give the ball away a bit, misplacing five of his first 10 passes as a United player. But then this is a part of his game.

He does ferret constantly after weak spots, improvising rather than playing the patterns. It is not hard to see a slight disjunct with Pep Guardiola’s tactical ideals.

He sprinted through the middle then did that thing where he just stops, instantly, like a cartoon mouse spinning on its heel and watching a pair of galumphing cats slide past, legs flailing. In the Screwfix there was a burst of nervous laughter at this guilty treat. OK. Fine. We’ll give you that one.

Five minutes before half-time Sánchez had a hand in the opening goal, carrying the ball inside, feeling the spaces open up around him and playing a nice pass into Marcus Rashford. He was allowed to carry the ball a bit too far by a dithering defence and finished neatly.

Early in the second half Ander Herrera added the second, helped by Sánchez’s pass, the best part of which was the sight of both him and Rashford haring off on a break with genuine, surging power, another sign of understanding between the two. More of this please, José, not less.

As there will surely be. For some reason there has been a debate about whether Sánchez represents value for money. In reality value has no room in this discussion. Value is what Arsenal were after, value is fourth place year after year. Sánchez is too wild, too desperate to win to worry about value or good sense.

He is, on the face of it, perfect for Mourinho too, a manager who loves high-impact bolt-on parts; who has found in Sánchez the perfect addition, a ready‑made nitroglycerin injection of a footballer, who began here as he means to go on.