Match ends, Hearts 0, Motherwell 1.
Motherwell held off a battling Hearts side to claim a sixth straight win and consign their hosts to a third straight defeat.
John Sutton ghosted in behind the Hearts defence to evade goalkeeper Jamie MacDonald and give the Steelmen a deserved lead.
But the home side improved in the second half with Ryan Stevenson's cross hitting the woodwork.
And Stevenson, David Smith and Jamie Hamill all had efforts saved.
The result moves Stuart McCall's side to within a point of second-place Aberdeen, while Hearts are now 20 points adrift at the bottom of the Scottish Premiership.
A save by Hearts goalkeeper Jamie MacDonald spared the blushes of team-mate Jordan McGhee early on, with the defender having turned James McFadden's low cross towards goal.
McFadden's guile unlocked the home defence moments later but Iain Vigurs' tame shot was easily gathered by MacDonald.
Motherwell were the more active side in attack throughout the first half and Lionel Ainsworth was eager to add to his tally of four goals in as many games.
The winger was foiled by Scott Robinson after racing in on goal and getting away a shot before his next effort flashed over the crossbar.
And the on-loan Rotherham player drew a superb save from MacDonald with a driven half-volley moments later.
But when the Motherwell opener did arrive, it was from a former Hearts player.
Sutton latched on to a Vigurs pass and, with the Hearts defence in disarray, the striker rounded MacDonald and clipped home, albeit with the help of a nick off defender Dylan McGowan's boot.
The procession of attacks towards the Hearts goal continued in the second half with Ainsworth's poor touch allowing MacDonald to clear following another inviting Vigurs through ball.
Hearts had struggled to make in-roads to Gunnar Nielsen's goal but Stevenson had the home fans on their feet when his cross clattered off the crossbar.
Nielsen then beat away David Smith's powerful blast, making Motherwell's lead look all the more slender.
Stevenson was next to test Nielsen and, from the resulting corner, Jamie Walker's rising effort flew just over.
Walker had another effort blocked by Nielsen and there were some more nervous moments for the Motherwell defence when a Hearts corner pinballed off a couple of heads in a crowded six-yard box.
Looking for a second to end the match as a contest, substitute Henri Anier buried a rebound shot after Sutton's initial effort had been well saved but a foul by Sutton meant no goal.
There was still time for Hearts to carve out another chance to level and Hamill took his time before poking a shot towards goal, only for Nielsen to block with his knees.
- 3McHattieSubstituted forWalkerat 54'minutes
- 18CarrickSubstituted forNicholsonat 73'minutes
- 12PatersonBooked at 77mins
- 17SmithSubstituted forKingat 80'minutes
- 3HammellBooked at 90mins
- 25AinsworthSubstituted forFrancis-Angolat 74'minutes
- 7McFaddenSubstituted forAnierat 74'minutes
- 11VigursSubstituted forLawsonat 84'minutes
- William Collum
- Shots on Target
Second Half ends, Hearts 0, Motherwell 1.
Steven Hammell (Motherwell) is shown the yellow card.
Foul by Steven Hammell (Motherwell).
Jamie Walker (Hearts) wins a free kick on the left wing.
Foul by Jordan McGhee (Hearts).
John Sutton (Motherwell) wins a free kick in the defensive half.
Attempt saved. Jamie Hamill (Hearts) right footed shot from the centre of the box is saved in the centre of the goal.
Corner, Motherwell. Conceded by Brad McKay.
Brad McKay (Hearts) wins a free kick in the attacking half.
Foul by John Sutton (Motherwell).
Substitution, Motherwell. Paul Lawson replaces Iain Vigurs because of an injury.
Substitution, Hearts. Billy King replaces David Smith.
Attempt missed. Ryan Stevenson (Hearts) right footed shot from outside the box is too high.
Corner, Hearts. Conceded by Simon Ramsden.
Corner, Hearts. Conceded by Steven Hammell.
Attempt saved. Callum Paterson (Hearts) header from very close range is saved in the top centre of the goal.
Corner, Hearts. Conceded by Gunnar Nielsen.
Attempt saved. Henri Anier (Motherwell) right footed shot from outside the box is saved in the centre of the goal.
Scott Robinson (Hearts) wins a free kick in the attacking half.