Roy Keane watched from the bench as Celtic three away a two-goal lead to secure only a point in a 3-3 home draw with Dundee United.
Wales striker John Hartson headed Celtic in front from an eighth-minute free kick by Japanese midfielder Shunsuke Nakamura before United levelled with a low shot by Spaniard and former Cetlic player David Fernandez five minutes from the break.
Pole Maciej Zurawski nodded Celtic 2-1 ahead from Shaun Maloney's cross and Bulgarian Stilian Petrov marked the signing of a new contract that will keep him at the club until 2009 by firing in a 25 yard effort with the help of a deflection.
Dundee’s Lee Miller pulled a goal back for United before Fernandez converted an easy chance to equalise and earn his side a deserved point.
Elsewhere, second-placed Hearts hammered Hibernian 4-1 in the Edinburgh derby.
Paul Hartley hit a first half double, one from the spot, while Czech Republic striker Rudi Skacel made it 3-0 against 10-man Hibs, after Gary Smith was sent off before halftime following an off the ball incident.
Calum Elliot scored Hearts's fourth before Garry O'Connor pulled one back for Hibs.
Celtic top the table with 58 points from 24 games while Hearts have 50 from the same number of matches.
Champions Rangers, 18 points behind the leaders, play at Inverness Caledonian Thistle tomorrow.