Harald Brattbakk celebrated his first start for Celtic in almost three months by grabbing a hat-trick at Parkhead tonight.

The Norwegian's three goals helped the hosts to a comfortable victory over St Johnstone and kept alive their flickering hopes of retaining the Scottish League title.

Celtic are 13 points behind leaders Rangers despite this handsome win, but the manner of this victory will surely give them heart.

Saints came into the match only one point adrift of Celtic in fourth place and aiming to chalk up their third victory over the Glasgow club this season.

But in the end they were outclassed after making a bright start to the game.

Miguel Simao squandered a great chance of giving Saints the lead after just 30 seconds.

The Portuguese striker was left clear in the penalty area after a delightful through ball from Keith O'Halloran.

But he took one touch too many, and Johan Mjallby was able to get in a vital tackle and divert the ball to safety.

It proved to be a crucial miss, with Celtic taking a grip on the game in the space of 20 minutes.

Brattbakk marked his first start since November 3 by making the breakthrough in the sixth minute.

The Norwegian striker, preferred to Mark Burchill, got on the end of a cross from Lubomir Moravcik to steer the ball beyond goalkeeper Alan Main from six yards.

His effort seemed to take a slight deflection off John McQuillan, but that didn't prevent Brattbakk wheeling away and saluting the fans.

Celtic stepped up the pace and added a second in the 19th minute with a goal that had a stamp of class written all over it.

Henrik Larsson cleverly held the ball up for Moravcik on the edge of the area, and the midfielder's shot was unstoppable.

Simao should have put Saints back in the game when John O'Neil set him up after a surging run but he succeeded only in rattling the top of the bar in a good position.

Celtic had no such problems in front of goal and surged 3-0 ahead after 31 minutes after an incredible scramble. Larsson scored his 21st goal of the season after a chain of events that left the crowd catching their breath.

Brattbakk's shot was beaten away by Main, as was the rebound from Phil O'Donnell.

The ball broke to Moravcik, who rattled the bar, leaving Brattbakk to head it across the face of the goal, where Larsson delivered a powerful diving header.

There was no respite for Saints, who had been riding high in the league despite conceding seven to Rangers earlier in the campaign.

Vidar Riseth tested Main in the 53rd minute with a header after Alan Stubbs had launched a long ball forward.

Then Larsson went round the hard-pressed goalkeeper after O'Donnell played the ball through only for Darren Dods to make a timely interception.

But Saints caved in again in the space of two minutes as Celtic extended their lead.

Larsson and Brattbakk linked up, and the Norwegian timed his run to perfection to score his second goal of the game in the 78th minute with a shot that went under Main's body.

Brattbakk completed his hat-trick two minutes later with a tap-in at the far post following a pass from Larsson across the face of the goal.

Celtic are now only four points adrift of second-placed Kilmarnock and are still in contention.

Poor Saints looked as though they had been mugged, and it remains to be seen whether they can still enter the bidding for a UEFA Cup place.

Teams:

Celtic: Gould, Boyd, Mahe (Hannah 73), Stubbs, Larsson, Brattbakk, O'Donnell (Blinker 79), Lambert, Moravcik, Riseth (Donnelly 84), Mjallby.

Subs Not Used: Burchill, Corr.

Booked: Mjallby, Moravcik, Lambert.

Goals: Brattbakk 6, Moravcik 19, Larsson 31, Brattbakk 76, 78.

St Johnstone: Main, McQuillan, Kernaghan, Scott, O'Neil, Kane (Griffin 82), McMahon (Connolly 68), Bollan, O'Halloran, Dods, Simao.

Subs Not Used: Grant, Robertson, McAnespie.

Booked: O'Neil, Kernaghan.

Att: 60,092

Ref: J Rowbotham (Kirkcaldy).