Aston Villa's chances of automatically qualifying for the Champions League round of 16 are now hanging in the balance after losing 1-0 to Monaco in their penultimate league phase game at the Stade Louis II.

The defeat means Unai Emery's side will have to beat Celtic at Villa Park next week to give themselves the best opportunity of finishing in the top eight of the league phase table and avoiding a two-legged knockout play-off.

Wilfried Singo opened the scoring in the eighth minute when he headed in a rebound following a smart save by Emi Martinez as Villa failed to deal with a corner conceded after Tyrone Mings gave the ball away. Leon Bailey had the chance to score before Villa fell behind as he was picked out in the box by Lucas Digne, but the winger got his header wrong.

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Villa’s best chance of the half came in first half added time as Emi Buendia slipped Ollie Watkins in on goal, but the striker’s effort was saved by Radoslaw Majecki. Down the other end, Maghnes Akliouche also missed a big chance after he fired over from close range having been played in by former Liverpool man Takumi Minamino.

At the start of the second half, Watkins combined brilliantly with Buendia to find space to run into on the left, before he found Morgan Rogers in the box, but his finish flew wide of the post.

Emery introduced Jhon Duran into the action before the hour mark and he played up front alongside Watkins. It was Matty Cash who had the best chance in the final 30 minutes as he fired wide from a tight angle after being found by Rogers down the right.

Villa are back in action on Sunday when they entertain West Ham in the Premier League (4:30pm).

Player ratings

Emi Martinez

Booed every time he received the ball, Martinez made some brilliant saves in the first half, including one to deny Breel Embolo before Singo then scored the rebound. 7

Matty Cash

Cash played his position well, which was usually in a back three when Villa had possession. No doubt he wants to bomb on at every opportunity, but he understands Emery's structure well. When he could get forward, Monaco struggled to pick him up. He was picked out in an advanced position in the 70th minute, but his slice across goal didn't go in and there wasn't a teammate to tap it in either. 7

Ezri Konsa

Konsa took a heavy blow to his lower leg after Embolo landed on him in the first half, but he was OK to continue. He battled well against Embolo, who is a powerful forward, capable of rolling opponents. 6

Tyrone Mings

Mings gave the ball away which led to the corner which Monaco scored from. He defended excellently just before half-time when Akliouche tried to feed Minamino in the box, but the Villa centre-back snuffed the danger out. Made a vital block to deny Golovin in the 75th minute. 6

Lucas Digne

Digne was constantly an outlet on the left and he put in a great ball for Bailey early in the game, but the winger got his header all wrong. The Frenchman was replaced by Ian Maatsen with 25 minutes of the match remaining. 6

Boubacar Kamara

Kamara was often the foundation in which Villa played off after he won the ball back in the middle of the park. He also absorbed pressure from the Monaco midfielders to keep play ticking alongside Tielemans. 6

Youri Tielemans

Tielemans always looked to play forward and unlock either Rogers or Buendia in the pockets of space. In the 30th minute, the Belgian played Rogers in down the left, but the forward's cross for Watkins was blocked. It would've been a tap-in for Watkins had the ball found him. 7

Leon Bailey

Bailey didn't make the most of two chances he had to threaten in the box early on before Monaco's opener. His effort closer to the break was saved as he fired the ball at goal following a heavy touch from Watkins. Bailey threatened to make things happen, but it didn't go his way tonight. Replaced by Duran in the 56th minute. 6

Emi Buendia

Buendia was a surprise inclusion in the starting XI this evening as he made his third start of the campaign and his first in the Champions League. He was bright throughout, playing in off the left instead of down the middle. He found Watkins in pockets of space on several occasions and chased loose balls. He had a point to prove today and impressed. 7

Morgan Rogers

Rogers was a problem for the Monaco midfielders and defenders, who struggled to either pick him up or stop him motoring forward. He flashed an effort wide of the post at the start of the second period. 7

Ollie Watkins

Watkins was denied an equaliser just before half-time after a strong save from Majecki. Just after the second period started, he played a neat one-two with Buendia to then assist Rogers with another good chance. 6

SUBS

Jhon Duran (for Bailey, 57'): Duran put himself about, but didn't really get a sight of goal. 6

Ian Maatsen (for Digne, 67'): The left-back added more pace and direct running on the left flank, which was needed after Duran came on as Buendia still wanted to float inside the pitch. 6

Jacob Ramsey (for Rogers, 86): N/A

Lamare Bogarde (for Buendia, 86'): N/A

Subs not used: Gauci, Olsen, Nedeljkovic, Swinkels, Young.

GOALS

Monaco: Singo (8')

Villa: N/A

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