Warnock praised the forward's all-round contribution in the game, as well as his second goal in as many games.
The former Queens Park Rangers manager claimed that McCormack was the most likely to score for his side in the tight game at Elland Road.
"I thought if anyone was going to score it was Ross," said Warnock.
"It was a cracking goal, he deserved it and he covered lots of ground.
"He was a fraction away from putting one in at the end of the first half and looked very sharp."
McCormack joined Leeds from Cardiff City in 2010.