Unai Emery has revealed he was unconvinced by Mohamed Salah's ability to shine at a big club when he was presented with the chance to sign the Liverpool forward during his time as Paris St Germain boss.

The Gunners head coach will come up against Salah and his team-mates on Saturday, with Premier League leaders Liverpool looking to maintain their unbeaten season.

Salah has scored 59 goals in 78 matches across all competitions since moving to Anfield from Roma in the summer of 2017.

Emery was coach of Ligue 1 champions Paris St Germain at the time and, ahead of Arsenal's trip to the north-west, the Spaniard admitted he had been unsure of how Salah would cope at a big club.

"We spoke about the possibility to sign Salah to Paris St Germain when he was playing at Roma," Emery said.

"We had some doubts – and then he signed for Liverpool and these doubts he has broken at Liverpool. Now, if you are speaking about the five top players in the world, one is Salah."

Asked what the specific doubts were, Emery added: "Can he take the performance into one big team?

"For example like PSG in Paris. And today I can say to you...if we signed him, we signed one player in the top five in the world."

Emery highlighted the signing of Salah – and the later addition of centre-back Virgil van Dijk – as key moments in Jurgen Klopp's development of his title challengers.

"I remember three years ago they had a problem in their defensive moments and bought some people – for example van Dijk – with a good investment and the result is we are looking at them today and their progress," he said.

"They are very strong in defence and also they are improving a lot when they bought Salah and now offensively they are a very big team.

"I think the Premier League is now the best and most important competition in the world for the teams, with Spain, maybe Italy and Germany.

"But I think here are the best teams and players and now the leader in the table is Liverpool – and it is because they are doing things very well."