Mikel Arteta says title-chasing Arsenal have had to be "different" while captain Martin Odegaard is sidelined by an ankle problem.

Odegaard has missed Arsenal's last six games with the injury he suffered playing for Norway last month, an absence that has forced Arteta to change his plans.

Arteta said on Friday that the midfielder was "working so hard" to return, but the Gunners boss could not pinpoint when he would be back in action.

Leandro Trossard has come in for the top-flight games missed by Odegaard, as well as the Champions League win over Paris Saint-Germain this week.

In a tweak to Arsenal's usual 4-2-3-1 formation, Kai Havertz has played alongside the Belgian in a two-man strike partnership.

Arsenal's ability to adapt in Odegaard's absence has helped them remain one of two unbeaten sides in the Premier League, sitting in third place just one point behind leaders Liverpool.

"We had to be different," said Arteta, whose side host winless Southampton on Saturday. "The impact Martin has in everything that we do, it was too big to try to replicate it with one player.

"We've tried to do it in a different way, adapting a few things, using players' qualities, players that can play in different positions and with the right chemistry around them.

"Maybe it took a game or two but then things started to flow a bit better. We found a way, but we still miss him."

He added: "We don't have Martin, there are all the things that we cannot do. But as well we have a big threat in other areas and we have to make the most of them."