Caley's run in second place in the Scottish Premier League came to a juddering halt at Fir Park, with 'Well leapfrogging them to become Celtic's closest challengers.
It proved to be a fifth defeat in six games for Butcher's men and he admitted they were looking jaded after conceding a late goal in their 1-1 draw with Kilmarnock in midweek.
"We were second best," Butcher said. "They showed more hunger and appetite for the game and got the goal at the crucial time.
"I thought we started the game very well. You could see our lads were a little bit leggy after the midweek game, they put a hell of a lot into the Kilmarnock game and there was a lot of heartache when we didn't win the game.
"There have not been many times we have come up second best against a team and unfortunately it has always been Motherwell.
"The pivotal moment was the first goal, we defended like amateurs. It gave them a lift and knocked us back."