Scotland and the Republic of Ireland are goalless in their Euro 2016 qualifier despite a frenetic first half in which Grant Hanley was lucky to escape a red card.
The Scotland defender hacked down Shane Long on 12 minutes as he threatened to go through on goal, but Serbian official Milorad Mazic did not believe that he had denied the Ireland striker a goalscoring opportunity and produced only a yellow card.
Perhaps that was a fair, with Long, who was preferred in attack to Ireland's record goalscorer Robbie Keane, having knocked the ball way ahead of himself, but Hanley could have been cautioned again when he led with his arm during an aerial challenge with Ireland stopper David Forde.
Amongst the controversy, there were several chances for either side as an early Jonathan Walters sighter called David Marshall into action, and the Scotland keeper also denied Darron Gibson from long range.
Steven Fletcher passed up a couple of golden chances for Scotland when he failed to keep down a free header from an early corner, and then somehow missed a Shaun Maloney cross just prior to the break.
Ireland winger Aidan McGeady, who, against the country of his birth, was loudly booed on his return to Celtic Park and failed to have an impact, but Andy Robertson was dangerous for the hosts on the same flank.
One of several inviting deliveries from the Hull City left-back seemed bound for Steven Naismith, but his clever run was well checked by Stephen Ward, who made a crucial block at the near post.
