Celtic and Fulham are stepping up their battle for Rosenborg defender Mikael Lustig.
The 24-year-old's contract expires in November and he will be available on a free transfer.
That has alerted both Celtic and Fulham, but Spanish side Espanyol have also joined the fight for a player who is a regular for his national side.
"We are in dialogue with a number of renowned clubs," said Lustig's representative, Lennart Norgen.