To be fair he also said it after the match in various interviews including this Sky one.
"“That was the benchmark of the league, the championship. Brighton were fantastic, physical. [They had] 11 men out there. They can play too. They play direct, they’re full of running, and that’s the...
Here's McClaren's interview from Radio Derby, although he said much the same to Sky after the game too.
http://www.bbc.co.uk/programmes/p04wh6cg
“They were excellent, not many teams this season have done that to us. (Newcastle ?) . It just shows how far this championship has gone. It was only...