Matias Soule bends one to the far post and Celtic keeper Kasper Schmeichel has to get down parry wide.

Evan Ferguson smashes the right-hand post from the edge of the area.

Celtic need to wake up here.

Kheredine Idessane
BBC Scotland at Celtic Park

Wilfried Nancy has his arms crossed in his technical area, watching on impassively.

He can't be happy with what he's seeing at the moment. There is no-one taking responsibility, little to no quality on the ball and a swarm of Roma shirts around anyone in green and white.

Gian Piero Gasperini? Like the cat who got the cream, hands in pockets, savouring the potential for his second win in Glasgow in as many months.

This is barely a contest. Celtic are miles off it and lucky to be only a goal behind.

Zeki Celik looks for the far post but totally slices his effort.

It's another shot from the visitors, though.

Pat Bonner
Former Celtic goalkeeper on BBC Sportsound

Nygren has been at fault a couple of times now.

Roma look dangerous every time they go forward.

Probably because Celtic keep giving them the ball.

Strasbourg striker Kendry Paez is the next name in referee Robert Schroder's book after a late, lazy clip on Nicky Devlin.

Kheredine Idessane
BBC Scotland at Celtic Park

Roma are comfortably superior so far in these opening stages.

A goal to the good, stroking the ball about at will, Celtic struggling to keep pace with them and barely able to get out of their own half.

There is a distinct lack of balance about the home side, who seem vulnerable every time Roma advance beyond the halfway line.

Which is frequently.

Image source, SNS

Celtic are yet to have a shot after 18 minutes at Parkhead.

Oh, well then. Mats Knoester's wait for a first Aberdeen goal goes on.

After a VAR check, the goal has been chopped off for handball.

On a replay, it looks like the defender marginally glances his header onto his arm first...

Image source, SNS

Celtic fans are getting a bit miffed with the referee, who has just got in the way of play but a drop-ball hasn't followed.

Oh Marko Lazetic should have Aberdeen in front.

Stuart Armstrong threads through a defence-splitting pass, the striker's first touch is magic, pulling the ball away from the spinning centre-halves, but his shot lacks conviction and is blocked.

Big, big chance right in front of goal.

Image source, SNS

Image source, SNS

Stephan El Shaarawy cuts in off the left and aims for the far post but watches his effort bend wide.

Celtic struggling here.

Pat Bonner
Former Celtic goalkeeper on BBC Sportsound

That's where Celtic struggle.

They only have the two decent-sized centre halves. Everyone else is fairly small.

It's difficult when you're up against big players.

Seven minutes in and Mats Knoester has picked up an early yellow card for cutting off a Roma attack on the halfway line.

Walking a tightrope already...

Kheredine Idessane
BBC Scotland at Celtic Park

I wondered if Celtic might struggle at the back again with just three recognised defenders on the park.

Roma have just scored a similar goal from a corner to the one Hearts scored at the weekend.

A poor, scrappy, lethargic start from Celtic, who now have it all to do.

As starts to managerial careers go, this is as tough as it gets for Wilfried Nancy.

If his side don't wake up, this game could get away from them very quickly.

Roma have started the better, winning a corner after Celtic give the ball away cheaply...

It's fair blowing a gale up at Pittodrie, but in the opening stages it's playing in Aberdeen's favour.

A couple of Stuart Armstrong corners are cleared away, while there was a wee VAR check going on behind the scenes for a potential penalty, but it's been batted away.

Bright stuff from the Dons.