Just seven days after his brilliant four-goal display in the win over Hamilton Accies, English striker Moult had minimal impact during the 1-1 draw at Firhill and was substituted after 73 minutes.
“Moulty has not trained all week,” McGhee told pressmen after the final whistle.
“He hurt his hamstring when he stood on his child’s soft toy.
“That was a worry all week, but he declared himself fit this morning. He had a fitness test and he played.
“But that was why we took him off.
“Louis has not come off because he felt the injury. He’s come off because he hadn’t trained all week and I didn’t want it to recur.
“He is in form, he’s confident, he felt as if he could and should play so we gave him a go.”
McGhee said that ’Well were poor in the first half but came onto a game later.
“We weren’t connected in the first half,” he said.
“We didn’t have the sort of team performance that we’ve been having of late.
“We lost a really disappointing goal. Hammy doesn’t make those sort of mistakes so we’ll forgive him for that.
“But the second half was much, much better. We’ve dug in and scored two goals.
“I’ve just watched Scotty’s first one. It’s nothing like offside. It’s ridiculously onside which is disappointing.
“We could have won it but Thistle could have been two up before we were one each.
“Given the first half performance I think we’ll settle for a draw.”
McGhee said ’Well’s three pronged attack of McDonald, Moult and Bowman was still work in progress but it was good to have such strong attacking options.
“We’re still working that out,” McGhee said.
“I thought Ryan did well today. He gives you a different option but maybe they’ll be days like today when actually only two of them can play and one of them comes off the side.
“James McFadden did well when he came on. He nurses the ball, drops his shoulder, comes back inside and he has those subtle little touches.”