Manchester United won the match 2-0, after two goals by Ole Gunnar Solskjaer.
Roeder said: “Everyone, and I mean everyone, is finding it hard to cope with Cristiano Ronaldo.
“He picks up pace so quickly he could be an athlete. I certainly would not like to be a full-back trying to stop him.
“Along with Wayne Rooney and Thierry Henry, he is undoubtedly one of the most dangerous players in the Premiership.
“He doesn’t appear to have been bothered by anything that went on during the World Cup and it is amazing to think he is going to get even better.”