They don’t have the squad to play EL and the prem at the same time. Their players are burnt out, Soucek was probably their best player last season but looks well average this one, Rice has been outstanding in many games this season but difficult to do it all on your own, like us getting Skipp to do everything.
They have some other good players like Bowen and Antonio but the rest are mostly average mid table players, if they ran a purely Prem season they might have maintained their good form longer but EL, injuries etc seem to have been to much.