With City currently holding a three-point lead over United at the top of the Premier League, Thomas admits it’s a big ask for Sir Alex Ferguson's men - who have lost their last two games against Blackburn Rovers (3-2) and Newcastle United (3-0) - to go and win at the Etihad Stadium.
“City are unbeaten at home which makes it difficult, especially given the defeat at Newcastle. Don’t write United off though, because they can always surprise you," he told FourFourTwo.com
Now working as a commentator, Thomas also believes that United will be looking for revenge following the humiliating 6-1 drubbing they suffered at Old Trafford in October.
“This FA Cup tie is a different thing to the league. I think they’d like to have some payback because United are still hurting from that, especially fans.”
Having famously scored against Manchester City for the Red Devils in 1980, Thomas feels the tie could witness the emergence of a new cult hero at Old Trafford.
“I got the only goal in a 1-0 win over City, I know that feeling. Of course you can be a hero or equally you can be a villain, which may make some players nervous. Make no mistake about it, both sides' priority is the league, but neither side will want to lose this game.”
While the home side are considered favourites among bookmakers, Thomas says he would be content with a draw, but refused to rule his former side out.
“I’m not one to bet against United. They’re still hurting, and that’s often when they’re at their most dangerous in my opinion.”
