Everton striker on loan Ellis Simms scored on his first start for Hearts as Motherwell were beaten 2-0 at Tynecastle.
Simms scored from close range in the 58th minute to double the lead as third-placed Robbie Neilson’s side took a 10-point lead over their closest rivals in the Scottish Premiership.
Andy Halliday had scored the opener in the 37th minute and Hearts could even afford to rest key striker Barrie McKay for most of the game ahead of Tuesday’s Edinburgh derby.
Motherwell had a few good chances in the first half but Graham Alexander’s side paid the price for losing the ball in dangerous situations before both goals.
The visitors survived a first scare when Stephen Kingsley had a shot blocked after an indirect free-kick just inside the box.
January signings Ross Tierney and Liam Shaw both made their first starts for Motherwell and both were involved as the visitors otherwise got off to a lively start.
Tierney was smart in possession and nearly made Kevin Van Veen’s return pass, while Shaw headed for a decent opportunity.
Van Veen twice missed the target with Hearts on the back foot and Halliday had a header held by Liam Kelly on the other end.
Simms had a few chances to show his pace from behind but Cammy Devlin put too much on a forward pass, and the loan striker then went down after beating Kelly one ball deep before flying high on another chance.
Motherwell midfielder Barry Maguire was injured after making a tackle and was replaced by Sean Goss, who was guilty in the opener three minutes later.
On-loan Celtic midfielder Shaw lost the ball first in his own half, but Motherwell appeared to have avoided danger until Goss lingered on the ball in his box. Liam Boyce won it and Devlin rolled it for the unmarked Halliday to break through at home.
Van Veen missed Motherwell’s best chance late in the half when he sent a free header wide from six yards past a cross from former Hearts striker Jordan Roberts.
John Souttar did not return for the second half after receiving a knock earlier in a collision with Callum Slattery. Toby Sibbick has made his Hearts return following his latest move from Barnsley.
Hearts soon had chances to double their lead. Gary Mackay-Steven sent a weak effort straight at Kelly, who quickly made a point-blank block from Halliday.
The second goal came after Devlin won the ball over Shaw in his own half and moved forward. The Aussie fed Boyce, who played him through goal for Simms to take advantage.
Hearts broke again on Motherwell but Boyce couldn’t convert after rounding Kelly and an offside flag ended the attack.
Motherwell fans thought they might have had a penalty when substitute Peter Haring cynically tripped Slattery as the midfielder rushed into the box, but referee Craig Napier gave a free kick. Roberts’ effort hit the wall.
Craig Gordon ensured there was no late drama as he set about holding off Van Veen’s long-range strike and got his hands on a ferocious effort from substitute Justin Amaluzor.
Hearts travel to face Hibernian on Tuesday night in the second Edinburgh derby of the season. The game at Easter Road is live Sky sports. Motherwell is also away from home on the same night as they head to Paisley to take on St Mirren.