Some things simply meet expectations, others catch us cold, take us by pleasant surprise. Aston Villa have made a habit of doing the latter over the past couple of years. Take the supporters who ended up slurping a pre‑match pint and talking double pivots with the Prince of Wales in the Wetherspoon’s at Birmingham New Street in the hours before they travelled to the win at Everton last week, after the royal Villa fan attended an inaugural critical‑care conference in the city.

Nobody envisaged Unai Emery transforming Villa in double-quick time, to the point where a victory in Monaco on Tuesday will put them on the verge of qualifying for the Champions League last 16 in their first season back on this stage for 41 years. There were plenty of sceptics when the Villa manager plucked Morgan Rogers out of the Championship 12 months ago but he has proved a revelation, one of the Premier League’s best performers this season, repeatedly leaving opponents in a tailspin. And few predicted Youri Tielemans would return to the peak of his powers after signing on a free 18 months ago.

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Other players have taken the acclaim but Tielemans has been central to Villa’s success so far this season. Perhaps it should be no shock. At the age of 27 the Belgium midfielder is comfortably Villa’s most experienced player in European competitions, having made his Champions League debut aged 16 for his boyhood club Anderlecht. Emiliano Martínez’s understudy, Robin Olsen, is next on that list and then Donyell Malen, who signed last week from Borussia Dortmund. Tielemans has played more than 500 club games, and won 74 caps for his country.

After Villa landed to teeming rain in the Côte d’Azur on Monday evening, Tielemans found himself back in familiar surroundings given he spent two years in Monaco before moving to Leicester City in a £32m deal. He also won silverware with Leicester, scoring a wonder goal at Wembley to lift the FA Cup in 2021. Alongside James Maddison, Jamie Vardy and Harvey Barnes, Tielemans was a key cog in the Leicester team that exceeded expectations under Brendan Rodgers and should never have been at risk of relegation. It turns out Leicester were really not too good to go down. Next week Rodgers will face the task of stymieing his former player when he brings Celtic to Villa Park.

Just as that Leicester team were envied from all angles, this Villa midfield is a force. In some quarters Tielemans was cast unfairly as damaged goods, a creaking talent, though neither his professionalism nor his affable character were ever questioned. How he has made light of those suggestions. It is why Villa regarded his arrival on a free as a significant coup. No wonder now he is at the thrust of this side, again punching above its weight at home and on the continent.

Before signing him, Emery wanted to check Tielemans still has the appetite to push himself. “When I met him at his home [before he signed] it was very important to firstly know him as a man, about his life, how is his life every day, family, thoughts about football, his ambition to try to keep being important and he is showing it,” Emery says. “He is always ready to play, he is always focusing on each match, competing 100% to improve, to help the team, to follow our message.”

Tielemans has formed a fine partnership with Boubacar Kamara, another shrewd signing, on a free from Marseille, but flourished when pushed into the No 10 role at Arsenal at the weekend. Kamara, who is not short of elite admirers, is now probably worth £75m. Tielemans? He is proving priceless; only Martínez has played more league minutes for Villa this season.

Rogers has been a breakout star, while Jacob Ramsey, who has been tracked by Newcastle and Tottenham, has shown glimpses of his best after returning from a hamstring problem. John McGinn, Villa’s injured captain, is the heart of this side. Amadou Onana is an athletic, powerful pillar. It was Tielemans, however, who got Villa back on track at Arsenal with a brilliant header, displaying legs, hunger and bravery to pile into the box and pull a goal back at the Emirates Stadium. Ollie Watkins equalised eight minutes later. It was a takeaway that has understandably done wonders for belief.

Emery says: “For us, last year was the adaptation of him. It was very important how he adapted to us and how he was understanding how we wanted to build with him and this year I think he is playing consistently and again in a different position because he can play different positions. But his best quality is in his mind, his mentality.”

Watkins and Jhon Durán naturally possess stardust as prolific goalscorers but as the Monaco manager, Adi Hütter, highlighted, another player keeps them ticking. It felt fitting given the pitch adjacent to Monaco’s Stade Louis II Stadium was renamed in honour of France’s most famous water carrier, Didier Deschamps, whose longtime base is a few miles along the coast at Cap d’Ail.

“Martínez is an unbelievable goalkeeper, Rogers is a fantastic No 10, Durán and Watkins as strikers,” Hutter said. “But Tielemans is the pacemaker in the centre of midfield.”