Celtic are ready to ramp up their interest in Hajduk Split midfielder Niko Sigur as the club looks to strengthen their options in the middle of the park. Mika Baur is due to travel to Glasgow after Celtic and Paderborn reached a compromise over a transfer fee; Sky Sports reports £4.5m, with a further £2.3m due in add-ons. With Hajduk demanding a significant fee and other clubs watching Sigur, Celtic will have to decide quickly just how serious they are about landing one of their midfield targets.