In the playground of the rich and famous, Aston Villa were left ­counting the cost of a sluggish start. The Prince of Wales and Nassef Sawiris – the Villa co-owner whose superyacht would not look out of place round the corner at Port Hercules – were among those in ­attendance in Monaco. Villa roused but never truly recovered from Wilfried Singo’s early headed goal and their hopes of qualifying automatically for the last 16 will go down to the wire when Celtic visit next week.

An hour before kick-off Unai Emery was serenaded by the Villa supporters stationed under the iconic arches of this stadium on the French Riviera, but this was a rare night when his side fell flat, a mirror-image of their result at Club Brugge in November and reminiscent, too, of that pale display.

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This is an opulent but strange place – not too many grounds are located opposite a Lamborghini showroom and a Ferrari service centre – and this was a puzzling, lethargic Villa perfor­mance. Emery was so miffed that afterwards he accused some of his players of going off-script.

Jhon Durán entered 11 minutes into the second half in place of Leon Bailey, partnering Ollie Watkins in attack, but Villa failed to heighten the workload of a Monaco defence who were never really stretched.

In the final minute of first-half stoppage time Watkins forced ­Radoslaw Majecki into a fine save after Emi Buendía – who shone on his first start since October and only his third all season in all competitions – squeezed the ball into the Villa striker under pressure. Bailey had Villa’s first notable effort, testing the Monaco goalkeeper after getting a shot away when off balance.

Buendía was one of few bright takeaways for Villa. He showed a creative spark that was otherwise lacking from a Villa perspective. For Monaco, who moved level on 13 points with Villa, there were plenty of positives. “I am really happy with this victory,” Monaco’s head coach, Adi Hütter, said.

“We are in a difficult situation but what the team did, big, big praise because they fought from the beginning to the end. They suffered a lot against a top team from the Premier League. To get 13 points and qualify for the knockout stages was one of our goals and we are very happy to achieve this.”

Before the game Emery alluded to Monaco’s pool of exciting youngsters and the 19-year-old Eliesse Ben Seghir and the 22-year-old Maghnes Akliouche were both influential in flummoxing Villa. Emery’s side ­finished the first half strongly after conceding on eight minutes. While Watkins failed to take his chance, Monaco equally should have doubled their lead with the final action but the lively Akliouche scooped over at the end of a swift counterattack.

Villa struggled to penetrate the hosts in the second period and ­presumably the manner of ­Monaco’s goal gnawed at them. It bothered Emery. Takumi Minamino intercepted Tyrone Mings’ loose pass out from defence, forcing Ezri Konsa to make a block and Monaco struck from Lamine Camara’s subsequent corner.

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Emiliano Martínez, whose every touch was jeered by the locals for his World Cup final antics against France in Qatar, repelled Thilo ­Kehrer’s initial header but was power­less to prevent Singo heading in close to the goal-line. A few minutes later ­Martínez made a smart save to prevent Akliouche’s first-time effort fizzing into the top corner from Ben Seghir’s smart squared pass.

Villa finished the first half brightly but the introduction of Durán, who formed a lesser-spotted partnership with Watkins, never worked the Monaco defence. Morgan ­Rogers sent a shot wide early in the second half and Matty Cash sent a com­fortable header at Majecki.

The best opportunity, though, was missed by Monaco. After latching on to a neat Akliouche through ball, Minamino selfishly went in pursuit of goal when he had the Switzerland striker Breel Embolo free to his left. It was Villa, however, who were left wondering what might have been.