Aston Villa will learn in the coming days if they will be punished by UEFA for the bottle thrown from the crowd at referee Jose Maria Sanchez.
The Spanish official had angered Villa Park with some of his decisions during the 3-2 win over Paris Saint-Germain on Tuesday, which saw Villa knocked out of the Champions League at the quarter-final stage, 5-4 on aggregate.
As Sanchez walked towards the tunnel at full-time, a plastic bottle was launched in his direction from the stands, narrowly missing him.
Supporters found to have committed such misdemeanours usually face life bans from clubs - or at least significant ones - if they can be identified.
Villa were also furious that only three minutes were added as they pushed for the goal that would have taken the tie to extra-time.
Now Villa face a crucial week, with Premier League fixtures against Newcastle and Manchester City before they face Crystal Palace at Wembley for a place in the FA Cup final.
Two victories in those Premier League matches will improve Villa's chances of reaching the Champions League again next term.
Midfielder Youri Tielemans said: 'I think the recruitment in January was really good, the players coming in have been showing their level, showing a good mentality.
'I think when you have new players coming in it raises the level and you can see tonight some of the quality that we had and obviously in other games that we've had as well.
'So now it's up to us to keep pushing and be back next season.'