By Clive Lindsay

Riordan is reportedly looking for a new club in January

Out-of-favour Derek Riordan saved a lacklustre Celtic with a late equaliser that denied St Mirren their first win at Parkhead since 1990.

A Jiri Jarosik header struck the inside of a Saints post as the game improved after a first half of few chances.

Billy Mehmet dispossessed Paul Hartley after 74 minutes, the Saints striker's shot was parried by Mark Brown and Stephen McGinn fired into the net.

But sub Riordan turned inside his marker to fire home 11 minutes later.

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The former Hibs forward is thought to be looking for a new club in January after a frustrating time at Celtic Park but saved a point for his present club that puts them two ahead of inactive Rangers in the Scottish Premier League.

Brown had started in goal for Celtic due to Artur Boruc's knee operation, while Jan Vennegoor of Hesselink came in for the injured Massimo Donati.

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St Mirren boss Gus MacPherson made four changes to the side crushed 5-1 at home by Falkirk.

John Potter, Chris Birchall, Garry Brady and Stewart Kean made way for McGinn, Alan Reid, Mark Corcoran and Ian Maxwell, who was making his first appearance of the season following a knee injury.

And St Mirren's containment exercise appeared to work against a Celtic who were somewhat subdued despite their dominance of possession after their midweek progress in the Champions League.

Hartley drove a free-kick straight at Buddies goalkeeper Chris Smith.

But Saints probed on the break and Corcoran's powerful effort from long-range deflected wide off Scott Brown.

Celtic winger Aiden McGeady curled a free-kick into the side-netting, but the players appeared to welcome the half-time respite from the sleet and snow and jeers of the home support.

Stephen McGinn (left) had put St Mirren ahead in Glasgow

The home side continued to press after the break and a glancing header from Jarosik struck the inside of a post before being hooked clear following a Hartley free-kick.

Former Celtic youth David van Zanten did well to block a Vennegoor of Hesselink header from eight yards out after the Dutchman was found by a Scott McDonald cross.

St Mirren had a claim for a penalty rejected when Corcoran went down on the edge of the box.

And McDonald just failed to make contact with an attempted shot on the turn from five yards.

Celtic paid for that immediately when Mehmet powered past Hartley.

The striker's shot was pushed into the centre of the penalty box by Brown and McGinn - the grandson of a former Celtic chairman - fired into the empty net from 15 yards.

Celtic pressed for an equaliser and Smith did superbly to tip a deflected McGeady shot over the crossbar.

And, when Evander Sno's long ball found Riordan, he controlled the ball superbly before curling it home from eight yards.

Celtic: Mark Brown, Caldwell, Pressley, McManus, O'Dea (Riordan 70), McGeady, Hartley, Scott Brown, Jarosik (Sno 56), McDonald, Vennegoor of Hesselink (Killen 86).
Subs Not Used: McGovern, Zurawski, Caddis, Balde.

Booked: McGeady.

Goals: Riordan 85.

St Mirren: Smith, van Zanten, Millen, Reid, Miranda (McCay 79), Maxwell, Murray, McGinn (Brady 76), Mason, Corcoran, Mehmet (Kean 86).
Subs Not Used: Howard, Potter, Burke, Barron.

Goals: McGinn 74.

Att: 55,747

Ref: C Richmond