Celtic manager Neil Lennon has admitted that his players have yet to reach peak fitness levels ahead of the new season.
A 1-0 win over Elfsborg on Wednesday night earned Celtic a slender advantage in their Champions League qualifier, but Lennon believes that his side would have performed better if they had more time to prepare for the fixture.
The 42-year-old told Sky Sports News: "We could have done with an extra week, especially for the European qualifiers, because there is so much riding on them this year.
"It would be fantastic if we could make the group stages, and a week in pre-season is very important and a long time.
"But having got through the first game with a clean sheet, the boys will be better off going into the game in Sweden."
Celitc begin their domestic campaign on Saturday with a home match against Ross County.