Costa feeds off the negative energy of others, Dier says, and that's why ignoring him can often work best for the Tottenham midfielder - and anyone else who comes up against the Spaniard.
Indeed, Dier is quoted as saying by the Mirror: "You just don’t get involved with him. I think he feeds off it and it helps him so the best thing to do is worry about playing your own game.
"These are the best games to play in and we are looking forward to it. The fans are too so hopefully we can give them something to be happy about."
Dier famously came up against Costa during the Capital One Cup final earlier this year and didn't give him any ground when the pair squared off against each other.
Costa ultimately prevailed in terms of football that day but Tottenham claimed their own victory over the Blues earlier in the calendar year when they beat them 5-3 at White Hart Lane.
Spurs are favourites going into this clash if you look at the formbooks but that's often when Jose Mourinho thrives. Whether Costa will play a part this time - and be anywhere near as effective - remains to be seen.
Dier, meanwhile, might not necessarily face him directly after moving into a defensive midfield position.