Celtic defender Efe Ambrose is a target for German Bundesliga side Bayer Leverkusen.

SportTimes understands the Nigerian centre-half is high up on the BayArena side’s wanted listed with representatives in Germany signalling ahead of a campaign in the Champions League that a £1.5m bid may be forthcoming.

The 27-year-old currently has a year left to run on his contract at Parkhead but Celtic will be reluctant to part with Ambrose without having someone coming in to replace him quickly ahead of a crucial stage of their season.

Read more: Celtic prove they are clever clogs for Brendan Rodgers after first win

The Ladbrokes Premiership winners begin their Champions League qualifiers next week without Dedryck Boyata, Jozo Simunovic – who are both injured – and Charlie Mulgrew, who is yet to agree a new deal.

There was no sign of Ambrose yesterday as Celtic won 1-0 away to Sturm Graz in what was their second game of their pre-season training camp. Visa issues have halted the centre-half meeting up with his team-mates due to fly out to Maribor.

“We’re still waiting to hear on whether he’ll be here,” said Brendan Rodgers, the Celtic manager after yesterday’s victory. “We’re just waiting on that.

“Well, having as many players as possible helps. But the boys who are out here are doing very well. We talk about the aggression in our defending and I was pleased with our corners tonight.

“We talked about having that bit of steel when we’re under pressure from a set piece.

“We defended that well, had good organisation. And, all round, our central defenders are coping well.”

Read more: Sturm Graz 0 Celtic 1: Familiar feeling provides comfort for Rodgers as Celtic's outlook changes

Meanwhile, Celtic goalkeeper Craig Gordon was pleased with a productive performance from the Bhoys during yesterday's 1-0 win in Graz.

Gordon, who played the second half, told Celtic TV: "In the first half we were pretty good and we probably created a few more chances then than in the second half.

“Overall, it’s a good win & a clean sheet, which doesn’t often happen in friendly matches, so we have to take the positives.

“It was probably the coolest day we have had since we have been here and it was nice to play under those conditions.

“It’s probably quite unusual for me to have played 2 friendlies already, normally I have to wait to later in pre-season.

“I feel fine and my body is holding up pretty well with all the training sessions we have been doing and the games.”