Gauld had a hand in all four goals as McNamara's men saw off nine-man
Thistle 4-1 who had Conrad Balatoni and Stuart Bannigan both red carded.
McNamara is hopeful the 17-year-old, who has been linked with Manchester United, will not be out for long after suffering a heavy knock during the game.
The United boss said: "Ryan took a knock towards the end and it's a bit early to know.
"He's taken a bang rather than a twist so hopefully it's not too bad.
"The physio and the doctor are assessing him now, they've got him iced and we'll have to wrap him in cotton wool.
"It might be a few days before we know where we are with it. Every United fan will be hoping he's okay.
"He was outstanding, he was involved in every goal.
"I've not worked with a talent like that before. He's something very special.
"His weight of pass, his decision-making and everything. He sees things before
anyone else in the stadium can see it.
Partick manager Alan Archibald refused to make excuses for his side's heavy defeat at Tannadice.
Archibald said: "We were lucky to get in 1-0 at half-time because we didn't
"You saw the real us for the first 25 minutes of the second half when we got a
foothold in the game.
"But we were too eager and gave up too much space. We made the wrong decision and they picked us off.
"United are good going forward but we let them cause us problems."