The Argentine winger made 67 appearances and scored 21 goals for Roma in Serie A between 2011 and joining us in August, 2013.
Now he's back in Italy and preparing for a big match in Florence with the tie poised at 1-1 from last week's first leg at the Lane.
There was huge interest as Erik sat down in front of the Italian media ahead of training on Wednesday night.
"We know this is going to be a difficult game but we will try to play our game, our football," said Erik, who has contributed two goals in seven appearances (three starts) in the competition so far this season, including his famous 'Rabona' goal against Asteras Tripolis.
"We're confident that we can play a big game.
"We know Fiorentina are strong and they will go out and play like they always do. I believe it will be an open game and as I said, we'll try to play our way."
Asked if it was difficult not looking beyond Fiorentina and ahead to Sunday's Capital One Cup Final, Erik responded: "That's another game, of course, a very important game but first we have to focus on Fiorentina. That's our only focus now.
"I think we're doing well, we have the skill to do well, we're improving and we'll try to keep improving."