Dean Smith called his strikers into a video session this week to show them how to run smarter and finish sharper. But Mason Greenwood gave them a demonstration of his own at Villa Park, scoring a goal of rare class to propel Manchester United closer to the top four and deepen Aston Villa’s relegation fears. Paul Pogba, with his first goal of the season, crowned the scoring with another immaculate finish and, if others had been as precise, United would have inflicted a heavier toll on their hosts. Although Ole Gunnar Solskjær’s team swaggered to victory in the end, Villa were entitled to fume about the way the visitors took the lead, as Bruno Fernandes began the beating with a contentious penalty. Villa must turn their minds quickly to Sunday’s clash with Crystal Palace, which could be critical to their survival hopes. United, meanwhile, have moved to within one point of fourth-placed Leicester. This was United’s game in hand on the teams above them and there was no good reason to suspect they would fritter it away. Their defence may still be vulnerable despite the side’s attacking resurgence but Villa hardly seemed like a team who could punish their flaws. Smith’s side had tightened up since lockdown but their problems now are at the sharp end. The three strikers available to Smith have scored one Premier League goal between them in their whole careers; United fielded an 18-year-old whose goal here means he has struck nine times in nine Premier League starts, taking his tally for the season to 17 in all competitions. His finish here was further evidence that he is already an expert marksman. And yet, this game started promisingly for Villa. Not only did Greenwood lose his footing when presented with his first opportunity, from a flick by Fernandes in the third minute, but Smith’s men rattled United with their pressing and the clever probing of Douglas Luiz in particular. Villa also had Jack Grealish, the one player in their ranks with the talent to be ranked alongside some of United’s luminaries. But Grealish is a diamond who has not sparkled since the league’s restart. Villa needed him to regain his lustre here and United had to keep a close eye on him, too, with Solskjær perhaps trying simultaneously to stifle him and appraise him. Grealish got a chance to make his mark in the 17th minute thanks to an inviting cross from the right by Ezri Konsa. But, after running on to the delivery, he failed to steer his volley on target from seven yards. That was as dangerous as Grealish got in the whole game. But Villa still threatened, and United escaped again in the 25th minute when Trezeguet struck a post from 20 yards. Just as Villa were growing in confidence and menace, their opponents were gifted a cheap chance to put them down. That has happened too often this season. This time, though, little blame could be assigned to Villa unless one agreed with Jonathan Moss’s interpretation of Fernandes’s fall in the box in the 27th minute. Unfortunately for Villa, the person with a variety of views, VAR official Graham Scott, did not see grounds for the decision to be overturned. Fernandes got up to send Pepe Reina the wrong way from the spot. That deflated Villa and had the opposite effect on United. Greenwood honed his sights with a fierce shot in the 35th minute that Reina did well to stop. Then Fernandes spared the hosts by heading wide from close range. And then, just before the break, Greenwood scored a remarkable goal. Receiving a pass at the edge of the area, he instantly shifted the ball on to his right foot and lashed it past Reina with the power and precision of a finisher who does not expect to be denied very often. Aaron Wan-Bissaka was less deadly moments after the resumption, when he made a fine burst to get on the end of a cross by Marcus Rashford but headed wide from six yards. Villa, though, already looked beaten. Pogba confirmed their fate in the 57th minute with another polished finish. Fernandes picked him out at the edge of the D with a well-aimed corner, and the Frenchman curled a perfect shot around a forest of bodies and into the bottom corner of the net. Reina did not realise what was happening until it was too late. Villa were at risk of disintegrating as United streamed forward. Martial nearly made it 4-0 but rammed a shot off the crossbar after being put through by Fernandes. Rashford was thwarted late on by Reina, showing that Villa’s resistance was not entirely shattered. They fight on but cannot afford to miss any more chances. It will take a much better team, meanwhile, to stop United and Greenwood from scoring.