Cristian Ledesma has tried to explain the secrets behind Lazio's success this season following Sunday's 2-0 win against Palermo.
The Aquile are still firmly entrenched in fourth place and show no sign of relinquishing their hold on the final Champions League spot.
Speaking to Sky Italia, Ledesma said: "Compactness was one of the secrets of our earlier games this season. Unfortunately we lost it for a little while, but now we have got it back again.
"It's a strange season. The derby is a game apart. Recent results in the derby will not count. We have always tried to do well against Roma. We will do so again on Sunday.
"Roma were built to go as far as possible in the table. We have to improve. We are up there and it's really important in this moment.
"We are a lot calmer with this victory."