Sampdoria's Antonio Cassano causes Inter concern ahead of Sunday's showdown.
The two sides battle on Sunday, and a win for Samp could take them within a point of their opponents.
And Eto'o believes Cassano is threat number one to discredit his team's chances of points.
"Cassano's Sampdoria? We have to be very careful with him on the pitch," Eto'o told La Gazzetta dello Sport.
"He is a unique player in his position, one that always does something different. He is unpredicatable.
"It will not be an easy game for us."