Kranjcar curled home a sensational free-kick two minutes from time to earn QPR a 2-2 draw at Loftus Road.
Ex-QPR striker Peter Crouch appeared to have handed Stoke boss Mark Hughes - who endured a torrid 10 months in charge at Loftus Road in 2012 - a happy return to the west London club when he fired the visitors ahead early in the second half after Steven Caulker had levelled Mame Biram Diouf's early opener.
However, Kranjcar had other ideas as he arced a fine set-piece beyond Asmir Begovic from 25 yards to ensure an under-par QPR snatched a valuable point.
And Redknapp was full of praise for the 30-year-old, who rejoined QPR from Dynamo Kiev on transfer deadline day.
"It was a great finish from Niko - he's got the quality to do that, he's a quality player," the 67-year-old, who has also managed the experienced midfielder at Tottenham and Portsmouth, said.
"When we got the free-kick I was hoping he could pull the game out of the fire for us and he did that.
"He was a free [transfer], we pay a third of what he earned in Russia [sic] - that's how much he wanted to come back. It's very rare to see a boy do that."
Redknapp - who confirmed that captain Joey Barton and midfielder Jordon Mutch both suffered hamstring injuries on Saturday - went on to express his satisfaction at claiming a draw.
"It's a good point today, make no mistake. It's a vital point," he added.
