Celtic have endured a frustrating evening so far at Parkhead after being held to a goalless first half with Kilmarnock in the Scottish Premiership.
John Guidetti was fouled on the edge of the area to give the home side a good chance from a free kick, but the Swedish striker could only fire straight at the wall before Kris Commons's dangerous cross was cleared on 20 minutes.
Commons's crossing again caused Kilmarnock problems and Mark O'Hara had to be alert to thwart James Forrest after another teasing delivery from the former Nottingham Forest midfielder.
Emilio Izaguirre delivered a cross towards Scott Brown before the half-hour mark, but the midfielder couldn't direct his header on target as Ronny Deila's men continued to press for the opening goal.
Virgil van Dijk came close for the Scottish champions on 35 minutes when he met a corner with a header that fizzed just wide, before Forrest curled an effort past the post.
Paul Gorst
