The Swedish defender has been plagued by injury problems over the past 18 months, with hip and groin issues sidelining him for lengthy spells.
Lustig made just five league appearances for Celtic last season and suffered a fresh blow in February when he damaged ankle ligaments in a Scottish Cup tie at Dundee which ruled him out for the rest of the campaign.
The 28-year-old has featured in all three of Celtic’s pre-season matches as they prepared for the first leg of their opening Champions League qualifier against Stjarnan at Parkhead tomorrow night. But Lustig is still some way from returning to optimum condition and has been told by doctors to expect discomfort for some time to come.
“The foot is still quite swollen,” said Lustig. “They say it’s going to be like that for a while so I just need to go through that. I am ready to go.
“It could be up to a year before it’s back to normal but it could be worse. Of course I don’t feel 100 per cent, but I can still give 100 per cent if you know what I mean. I take painkillers when we play the games, but not for training. I try not to do that. I have trained now for three weeks and it’s getting better.
“It’s been a frustrating time for me. I got some muscle injuries at the start of last season and when I got my second one, I thought ‘I need to do this properly and take a couple of weeks extra. I did that but then just two games after coming back, I got the foot injury at Dundee and was a little bit unlucky.”
Lustig, who is now in pole position to establish himself as Celtic’s first-choice right-back following the sale of Adam Matthews to Sunderland, is eager to play his part in an improved Champions League campaign this year.
He played in all six of last season’s qualifiers in which Celtic were eliminated in the play-off round by Maribor after a 6-1 aggregate defeat by Legia Warsaw in the previous tie was overturned due to the Polish club fielding an ineligible player.
Ronny Deila’s side conceded 23 goals in 14 European matches overall last season, compared to their miserly defensive record of just 17 in their 38 Scottish Premiership fixtures.
“We were a little too naïve in Europe last season,” said Lustig. “If we missed passes, we got punished more than we do in the Scottish Premiership where teams often go with ten men behind the ball against us. I remember the away game against Legia, we gave away two or three passes in the middle and they punished us with goals. We can’t do that again. But we are going to be more up for it this season and not as naïve.
“We want to play the ball a bit more with this gaffer than we did with our former gaffer (Neil Lennon). It’s going to take a while but that’s the kind of game we want to play. You need to try and do it in games. We can’t just do it on the training ground. We got punished for it last season but now we know more what he (Deila) wants. We know the way to play.
“The manager knows the team better. He knows our strengths and weaknesses – as a team and as individuals. That’s the most important thing. We also have Scott Brown back and he missed the first two months of last season. He is an important player for the team. We are definitely more ready this year.
“Stjarnan beat Lech Poznan, who won the Polish League, in the Europa League qualifiers last season but it’s all down to us on Wednesday night.
“If we play as we can, they shouldn’t be able to beat us but it’s football and crazy things can happen. But no, of course, we are going to go through this round. We want to get back to the group stage of the Champions League again but it’s really hard. We should have won against Maribor last season and made it. The away game, we should have scored at least three or four goals. Sometimes you can accept losing against a better team but we had a great chance against Maribor to get into the Champions League and we didn’t take it.
“Was it the low point of my Celtic career? Yeah, probably. You want to play Champions League football and we’d been given a second chance after what happened with Legia. We got Maribor and we thought we could beat them. This was a team we should have beaten but we didn’t. But hopefully we can get through this season.”