England’s meanest defence will face its sternest test yet this season on Sunday, as Saints go up against a red-hot striker rated as dangerous as Lionel Messi.

Sergio Aguero is expected to lead Manchester City’s attack at St Mary’s, with the Premier League’s top goalscorer fresh off a hat-trick in the club’s Champions League victory over Bayern Munich on Tuesday.

Aguero has netted 12 times in the top-flight this season, with Real Madrid forward Ronaldo (20) the only player in the major European leagues who can better that total.

Samir Nasri, Aguero’s teammate, said: “Ronaldo may be on another planet, but he (Aguero) is up there with Messi and [Luis] Suarez.

“He always delivers in a difficult moment.

“I think I don’t need to speak about his performance – the stats speak for themselves.

“He’s a great player. When he’s on his day he’s unstoppable.

“At the moment, he’s one of the best players in the world.”

However, finding the net this Sunday will be no simple task for Aguero, who is set to make his 100th Premier League appearance.

Saints boast the best defensive record in England, having conceded just six goals in their 12 top-flight games this season.

At St Mary’s, they have only let in one – to QPR’s Charlie Austin – giving them the second best home record in Europe’s top five divisions.

City have not had much luck on their visits to the south coast recently either.

They have failed to register a win in their last three trips to St Mary’s, with last season’s draw being preceded by a 3-1 defeat in the 2012/13 campaign.

However, it was around this time last season that City embarked on a stunning 12-game unbeaten Premier League run, in which they only failed to win one game.

That single blemish came when they visited St Mary’s, as Dani Osvaldo’s brilliant goal cancelled out an early strike from Aguero.

Nasri is hoping that City, who are unbeaten in their last three league games, can produce a similar stretch of form now.

“That’s what we need to do. We want to still be in the Champions League and be in the race for the Premier League.

“We have to have the same run that we had last year and let’s see in January where we are.”

Aguero, who has 17 goals for City across all competitions this season, has also underlined the importance of not dropping points at this stage of the campaign, given that they trail leaders Chelsea by eight and second-placed Saints by two.

“I am happy with my form,” said the former Atletico Madrid star, who moved to the Etihad Stadium for £38m in 2011.

“This season things are going well for me and it is important to carry on like this and keep the results coming.”