Helsingborg coach Age Hareide believes the key to Champions League success against Celtic is to stop the Hoops scoring in the first leg of their play-off in Sweden on Tuesday night.
The former Norway boss insists the Scottish champions are favourites to reach the group stages.
However, he does not think his side have to take a lead to Glasgow for the return game to have a chance of upsetting the odds.
Hareide pointed to the third qualifier against Slask Wroclaw, where Helsingborg went through 6-1 on aggregate after an impressive 3-0 first-leg win in Poland, when claiming a clean sheet against Neil Lennon's side was imperative.
"The most important thing is not to let Celtic score an away goal," he told Press Association Sport.
"That is the key to the tie. If they do score it will be very difficult for us.
"I have seen Celtic against Helsinki and against Aberdeen and they are a good team, a hard-working side" - Age Hareide
"We don't necessarily need to take a lead to Parkhead. We had a good experience in Poland in the second qualifier, we did really well there and we defend well when we stick together.
"Celtic are favourites, they are a big club with good players.
"But expectations are high in Helsingborg with regards to Europe and the fans will be behind us at home.
"We have a good record there, I think we have only lost one game in two years, so we are strong and we played very well in our last home game (a 7-2 win over Kalmar).
"It will be an interesting tie. Tactics are important over two legs and things can change from one game to the other but we have to go into the game in a positive manner."
Hareide insists nothing should be read into Saturday's 2-1 defeat away to Elfsborg in the league.
"We played well in the first half and were winning 1-0 but we lost our legs a bit in the second half," he said.
"We were playing on an artificial pitch which wasn't great.
"I also rested players for the game on Tuesday, some of them have played many games already this season.
"We will see who is fit today and get ready for Tuesday. We got the scouting report and we will make plans.
"I have seen Celtic against Helsinki and against Aberdeen and they are a good team, a hard-working side who are well organised and who can play different formations.
"Of course I know Thomas Rogne who is Norwegian and Georgios Samaras played for Greece against Norway when I was national team coach and we will have to watch him."
Lennon is conducting his own fitness tests today on skipper Scott Brown, Paddy McCourt, Gary Hooper, and James Forrest but believes all four "should be okay".
He said: "We are getting four back so that will augment the squad very well. They are four very good players."
Meanwhile, Johan Mjallby has confirmed that midfielder Ki Sung-yueng wants to leave Celtic.
The South Korean, 23, has not returned from playing for his country at the Olympics amid speculation Barclays Premier League side Swansea are poised to launch a £6million bid.
Assistant manager Mjallby said: "Ki is not travelling. He is keen to move on and the club is in discussion with another club so we have to wait and see what happens. I can't say who the clubs is.”
