It was the 21-year-old's first goal for the club and the only shot on target during an arduous encounter played amidst difficult foggy conditions.

The hosts edged proceedings and their dominant back three, led excellently by captain Jason Kerr, limited Killie to barely any clear-cut chances.

The visitors' best opportunity fell after 24 minutes when Kirk Broadfoot headed off the bar. Chris Burke's pinpoint corner arrived perfectly for the experienced Broadfoot to meet with a powerful header that beat Zander Clark but the ball rebounded off the bar to safety.

Killie believed they should have been awarded a penalty just after half-time when McNamara appeared to handle in the box.

After blocking Nicke Kabamba's header, McNamara threw himself to meet Greg Kiltie's shot and it appeared to strike his arm but after slight hesitation referee Gavin Duncan waved away the protestations.

As the game progressed, the fog descended on McDiarmid Park which made visibility incredibly difficult.

Killie threw on Eamonn Brophy in an attempt to salvage a draw but the hosts defended resolutely.

The Saints made the better start and after a Kilmarnock mistake, the impressive Conway fired an ambitious effort over the bar from 25 yards.

St Johnstone continued to press forward and after McNamara burst down the right flank, David Wotherspoon sent an off-balanced strike wildly over in the 10th minute.

Both sides played with extreme caution during the first half although Broadfoot was twice fortunate to escape being caught in possession when attempting unnecessary skill in dangerous areas.

Set-pieces appeared to be the best avenue for either team to score all evening. Conway found Stevie May with a near-post corner after 34 minutes but the diminutive striker's acrobatic flick only found the side-netting.

Callum Davidson will be delighted as St Johnstone made it three unbeaten in the Premiership as they moved level with Kilmarnock in the table on 14 points.