Paul Paton, perhaps still smarting from being embarrassed by James Forrest for the third goal, clatters into Tom Rogic just outside the Saints box and is booked.

Danny Swanson skips by Saidy Janko but the Celtic defender halts his progress and is booked.

Leigh Griffiths takes a tumble in the penalty area under a Richard Foster challenge, but referee Craig Thomson rules it was a dive and books the Celtic striker.

Pat Bonner
BBC Radio Scotland pundit at McDiarmid Park

"It was getting very frustrating for Celtic.  They weren't creating too much despite getting in behind the Saints defence so they needed something. That will probably settle them down and it could be a long afternoon for St Johnstone now.  They will have to do something different."

David Wotherspoon almost fires Saints level but his free-kick from the edge of the box is tipped over the bar by Craig Gordon.

Joe Shaugnessy is the man in the right place at the right time for Saints again, blocking Tom Rogic's shot from 10 yards out after neat wing play from Scott Sinclair.

Former Manchester City man Sinclair looks in the mood today.

A poor touch from Kolo Toure allows Danny Swanson to get in behind the Celtic defence. The ball eventually drops to Murray Davidson but his shot from the edge of the box is well wide.

Leigh Griffiths' corner is floated to the back post where Scott Sinclair is lurking but his volley is blocked by Richard Foster.

Image source, SNS

Tom Rogic has started the season in fine style and the midfielder's galloping run through the Saints defence is only ended when keeper Alan Mannus rushes out to smother the ball at his feet.

Kieran Tierney is fouled right on the edge of the left-hand side of the box. Scott Sinclair fires a cross/shot into a dangerous area but the ball drifts inches wide of the post.

Danny Swanson registers St Johnstone's first effort on goal from around 25 yards out but Craig Gordon makes a comfortable save.

Slick build-up from Celtic as Scott Sinclair sends Kieran Tierney down the left flank. He finds Tom Rogic who squares for Leigh Griffiths in the penalty area but Joe Shaughnessy makes a timely intervention for the home side.

Sainst have barely had a touch so far.

Pat Bonner
BBC Radio Scotland pundit at McDiarmid Park

"It looks as if Paul Paton is almost man-marking Tom Rogic, who is playing in that number 10 position for Celtic. He is almost standing on his heels and that could create gaps that Paton leaves that other players will need to fill."

The possession stats make grim reading for the Saints fans in the opening eight minutes:

St Johnstone 10% - 90% Celtic

Celtic stroking the ball around the sun-kissed McDiarmid Park surface in the opening minutes.

Slight wind at Celtic's back in the first half.

Kieran Tierney's cross finds Scott Sinclair but the striker's control lets him down in the penalty area.

And to sum up the size of the task facing Saints today....

Image source, BBC Sport

Tom English
BBC Sport Scotland at McDiarmid Park

"Glorious day in Perth. St Johnstone in great form but this is the ultimate test for them today."