The Urvalsdeild champions will head into the tie as the underdogs, but Sigmundsson is confident that the Icelandic champions can stage an upset against the Scottish Premiership champions.
“We are not afraid of Celtic,” Sigmundsson told The Scottish Sun. “Anything is possible in football. Of course we believe we can beat them, although we know it will be very tough. But yes, we believe.”
“They are a very good team with a great coach and great players,” he added on his side’s preparation for the tie. “It will be a challenge for us, but we will be well prepared.
“We will watch Celtic’s pre-season games and take a look at them to find out their strengths and weaknesses.”
No room for complacency
Despite Celtic heading into the tie as favourites, they cannot be complacent, especially as the first leg is at Celtic Park.
Ronny Deila’s side will need to win that game by a good margin, or else they could face a tricky trip to Iceland a week later.
The Bhoys failed to progress to the group stage of the Champions League last season, and they will certainly not want to repeat the same failure this term.
Stjarnan came close to qualifying for the Europa League group stage last season, and they will give it a go this time around as well.