SPL: St Mirren 1 Celtic 1
A controversial penalty from Paul McGowan made it four away games without a win for Celtic as they were held to a 1-1 draw at St Mirren.
The Hoops had been comfortably ahead through a sixth-minute Kris Commons header but a red card to Victor Wanyama and McGowan's spot kick ensured Celtic took just their fifth point in their past six matches on the road.
Celtic came out firing early on in Sunday's match and after only six minutes they took the lead after the home team failed to deal with a corner, allowing Efe Ambrose to gain possession on the edge of the area and chip the ball to Commons, who headed into the net from close range.
For the remainder of the first half it was all St Mirren with Paul Dummett, Connor Newton, Marc McAusland and John McGinn all failing to beat Fraser Forster in Celtic's goal.
The league leaders could have extended their lead with 10 minutes remaining in the half, as Beram Kayal cut the ball inside from the right to Commons but he was unable to trouble St Mirren goalkeeper Craig Samson.
As the game entered first-half injury time Neil Lennon was handed a blow as Commons suffered an ankle injury after a collision with Kayal.
With nine minutes gone in the second half, Celtic were reduced to 10 men when Wanyama was shown a straight red card after catching McGowan on the shin.
St Mirren finally drew level with 10 minutes left as Goncalves went down on the edge of the area under a challenge from Izaguirre, prompting the referee to point to the spot and McGowan fired home the equaliser.
The hosts could have snatched all three points late on but Gary Teale sent a long-range effort over the bar.
Celtic lead the Scottish Premier League by 13 points from Motherwell, while St Mirren moved above Hearts on goal difference and into 10th position.