But the Dundee United manager insists he did not realise how good the Rangers striker was until he saw him up close. Houston combines managing United with helping Craig Levein's Scotland and that has given him the opportunity to see the likes of Miller, Allan McGregor, Steven Whittaker and Lee McCulloch at close quarters in training.
Houston said: "I always knew Kenny was a really good player but it has not been until working with him for Scotland that I have realised just how good he is."
He added: "He is a fantastic finisher and when you watch him up close in training it seems so effortless to him.
"He just guides the ball into corners with the minimum of effort because it is natural.
"You saw that with his goal against Liechtenstein, which was a very difficult manoeuvre to score from there. But throughout his career he's scored from six yards and scored from 20 yards.
"He has pace in abundance, he works hard and when you match that up to his finishing he's a top striker.
"He's probably in the best form of his career at the moment so he's someone we'll have to keep an eye on.
"But Rangers have so much quality, and I've been impressed by every single one of the lads they've got involved in the Scotland squad, that you can't just focus on one man."
Source: PA
Source: PA