See weakness, exploit weakness. Unai Emery is a master at it, with Nuno Espírito Santo the latest top-flight manager to be outmanoeuvred. Aside from Aston Villa’s stutter in the middle, this was a glistening example of precisely what Emery has made a career of: homing in on, and taking advantage of, opposition shortcomings.

Sometimes modern football feels accessible only to PhD-holders, a myriad of spreadsheets and shifting shapes. Yet there also remains a beautiful simplicity to the game. Here, Villa merely exploited a mismatch that stood out like a lemon in a punnet of blueberries when the teams were released: Leon Bailey, Villa’s full-back tormenter, against an out-of-position Moussa Niakhaté. It looked like a disaster-in-waiting, and appearances were not deceptive. Not that Niakhaté was alone in his defensive incompetence.

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In making a triple half-time change, Nuno in effect flipped over the remaining managerial chess pieces and restarted. Centre-back pair Felipe and Murillo were bathing before their teammates. Both had been cautioned already, which explains how Niakhaté survived.

The switches were wholly necessary. Such was ease with which Villa had opened a three-goal lead, even the much-maligned, sweat-holding shirts they donned back in August would have remained dry.

In grabbing Villa’s early opener, Ollie Watkins drew level with Mohamed Salah on 24 Premier League goal involvements this season. Douglas Luiz soon added home league goals number eight and nine for the campaign. The Brazilian, remember, is a number six.

True, Forest caused a few tummy flutters either side of the break courtesy of Niakhaté and Morgan Gibbs-White. But home stomachs were soon soothed by Bailey, who grabbed a reward for another high-voltage outing.

It was a pleasing return to the ruthlessness Villa have lacked in their recent trio of consecutive Villa Park defeats. “We concentrated on personality and trying to control the game with our style,” explained Emery.

“It was a fantastic 90 minutes. First half, I was feeling comfortable and confident. The second half, we started with some doubt, but our reaction was fantastic.”

Latecomers were still being admitted when the touchline-hugging Bailey was left unoccupied by Niakhaté. A turn of pace and a deft touch through Murillo’s legs later, Bailey presented Watkins with a gimme. Felipe too was nutmegged by the cross: it proved a portal into a chastising afternoon.

In attempting to shadow Bailey thereafter, Niakhaté at least showed signs of real-time lesson learning. Yet, inexplicably, just before the half hour, he showed Bailey on to his stronger left foot, allowing the Jamaican to find Matty Cash’s smart underlap. Douglas Luiz soon rolled in, and Emery celebrated like a gym user on a pulley machine. Gibbs-White’s subsequent rallying huddle had little positive impact on Forest. From a recycled corner, John McGinn slalom-twisted into sufficient space to allow him to deliver a perfect cross. Douglas Luiz rose to meet it.

Forest had offered nothing resembling an attacking threat when, in first-half stoppage time, Niakhaté chested in a lifeline. Half-heartedly, the visiting supporters sang about a famous comeback.

Those cries grew soon after the break. Nuno had also introduced Divock Origi, and his first meaningful involvement was a shoulder drop and drag. His second was a precise pass that expertly found Gibbs-White’s diagonal burst. Game on.

Things became frenzied. What had felt like a canter began to scream catastrophe-in-the-making. For Villa, Youri Tielemans struck the base of a post. For Forest, Anthony Elanga then fluffed a glorious chance to level.

Eventually, Bailey restored Villa’s two-goal advantage, but the opportunity was presented by Andrew Omobamidele, another half-time arrival, who played a lazy short pass that Tielemans intercepted.

“It was too easy for the opponents to score,” Nuno said, although he was adamant that he did not regret his team selection.

“[Niakhaté] can do the job there,” he explained. “That was not the problem.” He also confirmed that Nuno Tavares would miss a significant period with an unspecified injury. Emery was more hopeful on Pau Torres, who was withdrawn at the break.

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Forest must continue to throw nervous glances at Luton, four points behind with a game in hand. And that is before any potential penalty for breaches of profit and sustainability rules.

The final whistle brought a huge home roar, one matched in volume only when it was announced that Manchester United had been defeated. Does the Champions League beckon? The Holte End thinks so.