The Spurs wide player had predicted his side would win this weekend because Harry Redknapp’s men are a better team than their west London opponents.
The Italian told reporters on Friday: “We respect his opinion and we'll see on Sunday.
“Obviously, I don't agree with him.”
Spurs have struggled to pick up points in their recent league matches but Di Matteo is sceptical that form enters the equation in cup competitions.
He added: “When you play a one-off game, it's difficult to say who's the favourite because of the form the team's in. The dynamic of the game is different.
“This is a decisive game. We are in good form. We've been getting some good results and the players are confident.”
Andre Villas-Boas’ former assistant, who only took the helm at Stamford Bridge at the start of March, now has to balance an FA Cup semi-final and a Champions League semi-final against Barcelona this coming week.
Di Matteo insisted his team selection would not be affected however, adding: “I will look at the team for Sunday and only think about what's best for that game - to win that game.
“Whichever team I select, they have to put in a collective effort to win the game. One player alone won't be able to do that.”
When asked if he would prefer to get to the Champions League final over an FA Cup final, Di Matteo stated: “I’d like both.”
Di Matteo and Co. currently sit sixth in the Premier League - two points behind Newcastle United, three points behind Tottenham and five points behind Arsenal.
Di Matteo believes, win or lose, that the top-four battle won’t be affected too much by the result on Sunday, saying: “Winning always has a positive psychological effect on individuals and the team.
“It would be a better outcome, winning, but I don't think it would have an influence on who will finish fourth."
Despite not being in contention for title-winning glory, Di Matteo is delighted to be fighting on other fronts in the final month of the campaign.
He continued: “It's the period of the season where you play for all the trophies, isn't it? We're very pleased to be involved in this.”