It's been suggested the two do not complement eachother.
Ivanovic told the London Evening Standard: "Demba is fantastic, Fernando also and we can work on playing both of them together. It's going to be great for the team.
"Yes [Fernando is up for the challenge]. All this pressure is familiar for Fernando. He has the support of every team-mate and it is important for him to score and work hard in training every day. They are not against each other, they can play together and help the team."