Butcher's first home game in charge of Hibs looked destined to end in defeat after Kris Dolan's individual effort had given Thistle a second-half lead.
But Collins rescued a point with a low drive past Scott Fox in the dying minutes of the match.
"James has been brilliant, he has been an inspiration in the last three games," said Butcher.
"He leads the line tremendously well, works his socks off and he has good ability. He is always willing to miss opportunities and get straight back into the box again to score.
"I was absolutely ecstatic for him when he scored because it was a great finish - and finally the ball had dropped to a Hibs player in the box."
Butcher feared his side would finish empty-handed after spurning some chances, but was glad their hard work finally paid off.
"In the end perseverance paid off. Perseverance is the word of the day for me but for a while I thought the goal was never going to come," Butcher said.
"They scored a goal out of nothing and you could see the confidence flooding out for them. It took a while for us to get back into it, but I think there was a kitchen sink in there towards the end as we threw everything forward."
Thistle boss Alan Archibald admitted the late leveller was hard to take, but still tried to remain upbeat about his team's battling display.
"It feels like a defeat, that is all it can feel like when you concede so late. It is a sore one to take," he said.
"We will take the positives out of it. I thought our players were fantastic and worked ever so hard. We were very good throughout and it is painful to have not won.
"It could have been 2-0 when Ross Forbes had a chance but he thought there was a handball and snatched at the chance. That would have won the game for us.
"Then we lose a goal that's just down to bad defending. If he [Collins] doesn't score, there is another Hibs player waiting. There are small margins and you have to defend until the final whistle."