The French-born Algeria international joins the Reds on a one-year deal for the upcoming A-League season. 

Matmour was most recently playing for 1860 Munich in the 2.Bundesliga, having joined from Huddersfield Town. 

The 32-year-old has spent the majority of his playing career in Germany, with stints at Freiburg, Borussia Monchengladbach, Eintracht Frankfurt and Kaiserslautern. 

Matmour is also a 30-time Algeria international, but has not played for the national team in over five years. 

"For me this is a new experience and I am very excited to play here for this club and in this country," Matmour said. 

“If I am honest, I did not know so much about the Hyundai A-League, but in the last two or three weeks I have asked many friends. 

“One of my best friends is Jason Davidson, who plays for the Australian national team, and I asked him about this team and the league and he told me only positives. 

“I know [Adelaide United coach] Marco (Kurz) from Germany and he has a very big reputation and is a very good coach. 

“He has a good style and good ideas for football and that’s why for me this a good combination.”