Motherwell maintained their superb home record and deepened Kilmarnock's relegation fears as the hosts strolled to a comfortable Scottish Premiership win.
Elijah Just and Tawanda Maswanhise both struck in the first half, with the second goal coming just 47 seconds after Kilmarnock midfielder Tom Lowery was sent off for a second bookable offence.
It was a double blow for Neil McCann's side, who applied themselves well in a frustrating first half.
They thought they had gone in front when Liam Polworth skipped round Calum Ward and tapped home, but it was chalked off for offside after a VAR review, and Tyreece John-Jules hit the bar with a powerful header.
After the break, Motherwell totally dominated and went three to the good when Ibrahim Said fired past visiting goalkeeper Kelle Roos from close range.
Lukas Fadinger made it four in the closing stages, finding the bottom corner after some intricate passing on the edge of the Kilmarnock box.
It could have been a larger margin of victory in truth as Motherwell's incredible form in front of their own fans continued.
They are unbeaten in their past nine home matches without conceding a single goal and are within four points of Rangers and Celtic, who play Dundee and Hearts, respectively, on Sunday.
Kilmarnock are without a win in 17 matches and remain in the relegation play-off spot, three points above bottom club Livingston and five adrift of St Mirren in 10th having played a game more.