The 22-year-old was the target of two full-blooded challenges from United enforcer Paul Paton inside five second-half minutes.
But he refused to let the home side's physical tactics deter him and grabbed the winner that handed the Dons a 2-1 win at Tannadice to keep them in third place in the Scottish Premiership, two points behind Motherwell.
McInnes said: "I thought it was just that Peter scored the winner because I thought he was outstanding.
"He took a lot of treatment, he had a few clatters going in on him. It's just reward that he's the one that comes up with the winner.
"I want him to be known for being a top player, a player who makes the difference in games, a player who scores goals and affects games in a positive way. He has the pace and movement and the biggest thing is his intelligence to create space."
United have now followed their six-game winning streak with three straight defeats.
But Aberdeen continue to impress and are hot on the heels of Motherwell as the race for second spot hots up.
"I'm delighted to have won that game," added McInnes.
"We deserved it but I was worried we may have run out of time. We kept knocking on the door and our desire and fitness levels got us through."