Saints manager Tommy Wright made all three of his changes at half-time on a dismal afternoon for the Perth side, who ended the contest with 10 men.

Boyd led the line from the start for Killie's second successive home match and could have had two goals within the first 10 minutes.

First, he thundered a header off the bar from point-blank range following a sumptuous Chris Burke cross, then he was denied by a strong left-hand from Zander Clark.

The Saints goalkeeper could do nothing soon after though, as one of his own players put the ball in his net to gift the hosts the lead.

The quality was in the delivery from Rory McKenzie as his corner was glanced towards goal by Killie captain Gary Dicker. Saints forward Kane was the unfortunate man who got the final touch to put the Ayrshire side ahead.

Kane soon looked to make amends as he smashed a drive narrowly over from 25 yards with Daniel Bachmann scrambling, but that was to be as good as it got for the Perth side as Killie put their foot on the accelerator.

The second goal arrived from the right foot of Boyd. He calmly converted from the penalty spot after Jason Kerr had handled his goalbound header. The forward celebrated like a man who had not scored in months. His last goal also coming from the spot in a November defeat to Aberdeen.

Wright sent on Blair Alston, Daniel Swanson and Liam Gordon for the second half, for Scott Tanser, Callum Hendry and Michael O'Halloran.

However, the changes made little difference as his side struggled to live with their lofty opponents.

A bad day for the Perth side was capped midway through the second half when Kerr was sent off following a second booking for a cynical tug on McKenzie.

Clarke's men should have had a bigger lead but they spurned several good opportunities against the visitors.

Boyd looked to have added a third but was flagged for offside, while McKenzie and Alan Power both forced Clark into good stops.

It proved to be easy in the end for the hosts as they earned a fifth clean sheet in six games to stay in third place, ahead of Aberdeen – who they face in a fortnight.

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