We meet the Serie A giants at the Lane on Thursday as the knockout stage of the competition gets underway in earnest, with 32 teams all vying for the trophy.
La Viola sit fourth in the Italian league standings heading into the first leg and are sure to pose a stern test.
That fact is not lost on Danish international midfielder Christian, who says there is no room for error from here on in.
“It’s a great tie, a really tough game,” he said. “Fiorentina are doing well in Italy and they are a strong team.
“It’s always exciting in the knockout stage and it’s win or lose now – nothing in between. Everyone wants to go through and hopefully we’ll achieve that.
“A number of teams have come down from the Champions League as well now and if you manage to win the competition you get a Champions League place, so everyone wants to do well.”