Aaron Mooy described Celtic’s offer as an “amazing opportunity” after sealing his return to Scotland and a reunion with former Australia head coach Ange Postecoglou.

Mooy has signed a two-year contract as Celtic made a double signing with the addition of German defender Moritz Jenz on a season-long loan from Lorient.

Former Huddersfield and Brighton midfielder Mooy left Chinese club Shanghai Port earlier this year and is looking to secure a place in the Australia squad for the World Cup in Qatar.

The 31-year-old had a spell in Scotland’s top flight with St Mirren more than a decade ago.

Mooy made 30 appearances for St Mirren in two seasons from 2010 with his only league goal coming in a Christmas Eve win over Rangers.

“I played for St Mirren when I was a youngster – that was a while ago – and I’ve always been back and forth to Glasgow because of family, so it’s an amazing opportunity and one that I couldn’t turn down,” he told Celtic TV.

“It’s an amazing feeling and I’m just so happy to be here. It’s a massive club with a huge history and I want to be part of it, so I’m looking forward to the challenges ahead.

“It’s always a bit stressful when you’re talking with a club, especially a club like Celtic because they’re such a massive club, so I’m delighted that it’s all done and I can get to work and hit the training ground.

“Ange was my coach for about three years in the national team so I know the standards he wants and I’m looking forward to working with him again.”

Celtic have an option to buy 23-year-old defender Jenz, who began his career alongside Celtic midfielder Matt O’Riley in the Fulham youth ranks before joining Lausanne in 2020 and signing for Lorient last summer.

“Since last year, I’ve been in touch with Matt O’Riley who’s been my best mate since we were younger and played together at Fulham and he told me a lot of great things,” Jenz said.

“He texted me immediately after he signed, telling me it would be nice to have me here. I’ve followed the season and how it went, and obviously it went really well for Celtic because they won the league.

“It’s always good to have a friend and someone who can help you to settle in very quickly and I’ve also met the lads and they seem like a good group of people, very open, very nice, so I’m looking forward to work and working hard and getting as far as possible with the team this season and achieve great things.”

Jenz, who described himself as a “physical and aggressive” player who “likes to play”, added: “At Fulham my coach was Peter Grant, who was a big player at Celtic and I used to listen to all the stories he told me of when he played – he played with Andy Thom, who was also here.

“So I always had an eye for it – a special club with a special logo, a special shirt and a special history, so there was always a desire to one day play for this club. I think maybe it’s destiny – I hope so.”

The signings augment the Celtic squad following the arrivals of Alexandro Bernabei and Benjamin Siegrist earlier this summer along with permanent deals for former loanees Jota, Cameron Carter-Vickers and Daizen Maeda.

Postecoglou said: “I obviously know Aaron from my time coaching the Australian national team and he brings with him a wealth of experience at both club and international level.

“Moritz is a player we’ve been aware (of) for a while now and I’m pleased that we’ve been able to sign him.”