Celtic and Spartak Moscow have finished the first half of their tie at Celtic Park 1-1.
Celtic made a nervous start to proceedings, knowing that they would need a better result against Spartak than Benfica get at Barcelona in order to make the last 16.
The Russian side had the better of the chances early on, having dominated the game in midfield.
Kim Kallstrom and Emmanuel Eminike both saw efforts drift off target in the space of a minute for the visitors.
Celtic's goal came against the run of play, Georgios Samaras setting up Gary Hooper from the edge of the box after 21 minutes.
Eminike continued to look threatening throughout the opening 45 minutes.
Spartak's equaliser came shortly before half time, when Brazilian striker Ferreira Ari found the target.
With Benfica and Barcelona goalless at the break, Celtic will need to look for a winner in the second half.
