The best chance of the half fell to Fox inside the box with only the 'keeper to beat but he opted to square to Tonner who was surrounded by defenders and the danger was cleared.
The sides went in a half time all square but it was Motherwell who proved the hungrier in the second half and had a great opportunity to take the lead when Law found himself one on one with the keeper but dragged it past the far post.
Half time saw the introduction of Jamie Weir who made a real difference in the final third and gave 'Well a real injection of pace up front.
However it wasn't long after that that Motherwell took the lead with Fox again on the breakaway and this time kept his composure to put 'Well 1-0 up.
This inspired 'Well to push on and go for more and following a corner Avon couldn't deal with the danger and the ball fell to Kevin Totten who at the second attempt managed to prod the ball past the 'keeper, 2-0 'Well.
Not long after that Weir's grit and determination earned a penalty after he was pulled down in the box. He stepped up to convert the spot kick to make it 3-0.
That was the end of the scoring but Motherwell's second half performance really showed that they have the potential to go far in the Cup and push for promotion this season.
Team - Wullie Felvus, Nicky-Ray Watson, Ross Galloway, Peter Tait, Brain Totten, Andrew MacKenzie, Kevin Totten, David Law, Stuart Jack, David Tonner, Gerry Fox
Subs - Jamie Weir, David McParlane, Chris Sinclair, John Anderson, Fraser McNeil
Goals - Gerry Fox, Kevin Totten, Jamie Weir(pen)
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Off the park, Motherwell FC CT would like to extend their appreciation to everyone who attended the Race Night on Saturday and helped to make it a successful night. Everyone's help was very much appreciated and a massive thank you to the sponsors for making the evening possible.