Brendan Rodgers has admitted that he was worried for the safety of Leigh Griffiths after the Celtic striker was targeted with missiles in their Champions League qualifier with Linfield.
The Hoops won 2-0 in Windsor Park on Friday in a match where the club did not take up their ticket allocation because of security fears.
A bottle was aimed at Griffiths after he had set up the opener with a corner and, later on in the game, he was shown a yellow card presumably for taking his time at a corner when more objects came his way.
Asked by Sky Sports News about concerns over Griffiths's safety, Rodgers replied: "I didn't quite see what it actually was but if that is the case then of course there is always a worry.
"It was maybe a bottle of some sort, but anything, whether it's a coin or a bottle or whatever, shouldn't happen. Players go on to the field and it should be a safe environment for them.
"Obviously it's not what you wanted to see. The game was played in good spirit, in the main. So it's not ideally what you would like to see. I thought it was strange him getting booked for it."
Linfield confirmed that they would be launching an investigation into the crowd disorder at the game.
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