Indeed it was fitting that Gros claimed the second which eased the home nerves as the Killie forward was responsible for three goal-line clearances with the visitors bombarding Kyle Letheren's goal in the first half.
But Motherwell's frustrations got the better of them in the closing minutes when firstly Fraser Kerr and then captain Keith Lasley were shown straight red cards for wild tackles on James Dayton.
Following a pretty even start Kilmarnock took the lead after 12 minutes. Ross Barbour out wide on the right drilled a low ball into the box only for Hammell's outstretched leg to deflect the ball past his own goalkeeper from 10 yards.
Motherwell then took the game to their opponents with style and pace. Letheren had to thank Gros, who popped up on the goal-line to clear Shaun Hutchison's powerful header.
Remarkably it took another clearance from the Killie forward on the half hour to deny Hutchison with a thumping volley eight yards in front of a packed goal.
Then from yet another Tom Hateley corner, Simon Ramsden's header was palmed on to the face of the bar by Letheren, leaving Gros to once again clear the ball out of the six-yard box.
It was the home side that doubled their lead after 71 minutes. Dayton on the left touchline put in an inviting cross and Gros powered a great header down and into the net past Darren Randolph from six yards out.
Motherwell were then reduced to 10 men six minutes from time. Kerr, having replaced Hateley only four minutes previously, was first to go for a wild swing at Dayton.
And three minutes later Lasley followed him into the dressing room following a similar challenge on the same player as Killie comfortable held on to their lead.
- Sports & Recreation
- Kyle Letheren
- Keith Lasley