Mikael Lustig: I performed like a Fourth Division player on Saturday - but Celtic will be ready for the Champions League

The Scottish champions were disappointing in the opening 45 minutes of their game in Amstetten and fell behind just before half-time when Joelinton won and then converted a penalty.

Brendan Rodgers changed all 11 of his players after an hour had been played at the Ertl Glas Stadium and the Scottish champions finished the run-out strongly.

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Moussa Dembele, playing for Celtic for the first time since suffering a hamstring strain in the William Hill Scottish Cup semi-final win over Rangers back in April, levelled from the spot in the 73rd minute and the game finished 1-1.

However, the right back is confident that both he and his team mates will be in peak condition by the time they come to play their Champions League qualifier against either La Fiorita of San Marino or Linfield of Northern Ireland.

“It was a tough day,” said Lustig. “It was really warm out there, but there was some sloppy play. It was good for our fitness with a lot of running, but unfortunately a lot of it was in the wrong direction.

“We gave away a lot of possession. We wanted to play better and pick our passes, but it was quite sticky. Still, it was really good in terms of our fitness.

“You lose a lot when you are away for a month. You go from playing well, then have three weeks out and you come back like a Fourth Division player. It takes three weeks to get back. Some of us have been in for a few weeks now, others just one week, so it’s going to take time.”

He added: “It was only a pre-season game, but the second half was a lot better. The boys who played in the last 30 minutes did very well. The manager spoke to us at the end. It was a good session and he wanted to tell the players that.

“We know it’s a very important few weeks for us and we need to be switched on straight away. We didn’t play our best football at this time last year. So we know we are probably going to be more confident a year on. It’s about getting fitter and being ready.”

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Lustig was pleased to see Dembele, who has featured for the France Under-21 side this summer, back in action for Celtic and was delighted that the 20-year-old, who netted 32 goals in 48 games last season, marked his return with a goal.

The Swedish internationalist is hopeful the Scottish champions can hold on to the striker, who has been repeatedly linked with moves to the Premier League in England, for the duration of the 2017/18 campaign.

“It was good to have Moussa back,” he said. “He’s been playing with his national team and looking good in training. Obviously he’s a good player. It’s nice to have him back and for him to score.

“Obviously, there will be a lot of talk. Last season he was great so it is good to see him back. Hopefully he’ll get fitter and fitter. He’s a really confident when he is put on the spot, hopefully we’ll see him doing that a lot this season.

“We want to keep all of the players, keep the squad intact and maybe add some players as well. But it’s football. If the right money comes in then we know the club have to think about it.

“We know if someone is sold then new players can come in. That’s the deal. But we want to keep this squad as tight as possible. The manager has said no one is leaving while we have the Champions League qualifiers. That’s been the case the last couple of years. We know how important Europe is so we will have to see what happens.”