The Aussie striker told BBC Sport: "In the past we've lost cheap goals very early which hasn't helped us, so we need to stop that.

"Once you go behind it's always difficult to get something back from the game."

Celtic have a miserable away record in the competition and will be seeking to avoid adding to a long list of defeats on the road.

McDonald said: "We know how difficult it's going to be, in Scotland we are used to having lots of possession and dominating games.

"And when you do give the ball away you get it back quickly or you're not punished for it."

The Socceroo also believes Celtic will need to show plenty of patience during the 90 minutes.

"But, teams like Villarreal tend to keep the ball very well, so we'll have to keep battling away and maybe be more patient than usual."