Hearts came from behind to defeat St Mirren and record consecutive wins for the first time this season.
The Scottish Premiership's bottom side were behind within a minute from a Steven Thompson header.
But Hearts were level four minutes later as Callum Paterson rose unmarked to head in from close range.
And, when Marc McAusland was ruled to have felled Dale Carrick shortly after the break, the defender was sent off and Jamie Hamill scored the penalty.
Hearts thereafter survived a couple of nervous moments against the 10 men from Paisley to boost their faint hopes of avoiding relegation.
The Edinburgh side, docked 15 points at the start of the season, had moved into positive points for the first time at the weekend.
Thompson had put St Mirren ahead after a minute at Tynecastle
But St Mirren, who drew on Saturday, started the more confident of two unchanged line-ups.
The visitors were ahead within a minute when Thompson rose above two Hearts defenders 10 yards out to head home from a Conor Newton cross.
Hearts' young defence looked full of nerves as the Buddies looked to stretch their lead, but some poor defending allowed the Edinburgh side back into the game.
David Smith's cross from the right took a deflection into the St Mirren penalty box, where Paterson rose unmarked to head the equaliser.
The visitors failed to learn their lesson and, when Sam Nicholson cleverly made room for himself wide on the Hearts left minutes later, the cross found Paterson in acres of space in front of the St Mirren goal.
However, this time the forward's header was close enough to Marian Kello for the former Hearts goalkeeper to produce a superb save that sent the ball onto the roof of the net.
St Mirren steadied themselves and ended the first half the more dangerous side once more.
Jamie MacDonald was beaten after McAusland stooped to meet a corner kick, but the defender's header from 12 yards came off the face of the crossbar and the goalkeeper also made a good near-post block to deny Adam Campbell.
Hearts came out after the break with renewed vigour and a Danny Wilson header was deflected off the face of the crossbar and Paterson's attempt to score on the rebound was blocked in front of goal.
However, the home side did go ahead through a hotly disputed penalty that led to McAusland's dismissal after Carrick crashed to the ground as he sped into the box with minimal contact from the defender.
Despite Hamill's confident spot kick giving them the lead, Hearts remained vulnerable and a fine Jim Goodwin free-kick was turned wide by MacDonald at full stretch, while Thompson flicked a great chance over the crossbar from three yards.
Carrick ought to have done better than fire off the face of the post at the other end after pouncing on a ball over the Buddies defence, but the visitors had even more chances.
St Mirren substitute Gregg Wylde was causing Hearts all sorts of problems, forcing a near-post save from MacDonald before finding Thompson in space at the back post only for the striker to loft his volley high over the bar.
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