Boss Brendan Rodgers believes the clean sheet Celtic take into their Champions League qualifier against Rosenborg on Wednesday night could be crucial.

The Eliteserien leaders, who are 17 games into their domestic season, were more than worth the goalless draw in the first leg of their third qualifier at Parkhead last week.

While the Norwegian club are said by many to be in the driving seat ahead of the return game at the Lerkendal Stadion, the Northern Irishman disagrees.

"We kept a clean sheet and home or away in the second leg, that is important," said Rodgers, who confirmed striker Leigh Griffiths and defender Erik Sviatchenko are back in contention after recovering from their respective calf and groin injuries.

"I said before the game last week that it wouldn't be won in that game.

"There is still another game to play, in Rosenborg.

"We expected another tough game tonight.

"We know we can score the goals that we need to qualify but we respect Rosenborg as a team halfway through their season, they have good quality and they will be a really tough opponent for us."

The former Swansea and Liverpool manager remains perplexed that the champions of Scotland have to go through two qualifiers and a play-off to make the group stages of European football's elite club competition.

"I first got the experience of it last year and it wasn't easy and it will be exactly the same this time"

He said: "I don't believe the team that wins the league should be in the qualification phase, it never used to be the case.

"But of course finance and money changes the game and that means countries and clubs like ourselves, one of the biggest, iconic clubs in the world, are having to go through six games in order to qualify.

"But it is what we have to do.

"I first got the experience of it last year and it wasn't easy and it will be exactly the same this time.

"It gets tougher next year and we have to live with that and do our very best to qualify.

"But we want the problem. If that's what it takes for a club like ourselves to qualify then we have to do that, so we can't complain."