In-form Lawrence Shankland slotted his 22nd goal of the season as Hearts edged St Johnstone 1-0 at McDiarmid Park.
The strike following a long ball from defender Frankie Kent after 55 minutes secured a sixth win in a row for the Jam Tarts and they are now unbeaten in nine in the cinch Premiership.
The closest Saints came to scoring was through a header from Nicky Clark but it was that man Shankland (pictured by David Mollison) who cleared the ball off the line.
Hearts enjoyed 53 per cent of the possession against 47 per cent from the home side and had 493 passes against 455 from Saints.
His 50th goal for the Tynecastle team moves Hearts on to 48 points from 25 games, 12 clear of Kilmarnock who beat Livingston 1-0 at Rugby Park.
St Johnstone are tenth with 24 points from the same number of games and the win sets Hearts up for their televised fifth round, Scottish Gas, Scottish Cup tie at the Excelsior Stadium against Airdrie on Sunday with a 5pm kick-off. It’s on BBC Scotland.
Elsewhere, Hibs were beaten 2-1 by pace-setting Celtic at Easter Road. Adam Idah scored from a penalty for the visitors after ten minutes, his first goal for the Hoops, but Dylan Levitt levelled on the hour.
Idah scored the game-winner also from the penalty sport in the second minute of injury time leaving Hibs seventh in the 12-strong table with 26 points from 24 games.
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