Saints will be able to judge where they are this season once they have gone head-to-head with Manchester United, according to Mauricio Pellegrino.

The Saints manager is relishing taking on what he one of the biggest clubs in the world when Jose Mourinho’s men roll into St Mary’s tomorrow.

After a mixed start to the campaign Pellegrino is keen to see his team up against one of the Premier League’s big guns and believes how they fare will be a significant marker.

He said: “It’s a nice opportunity. I see it as a huge opportunity for us.

“We will realise how we are against a top team and top quality players.

“I see this as a nice opportunity for us to show ourselves, show where we are and when we play against the biggest teams in the world to draw a conclusion about how we are.

“It’s a good challenge and we have to strive for this.”

He added: “We don’t know what will happen but I see this game as a nice opportunity to show ourselves how we are and to come against them.

“In team sports you have something really nice and you can win against everybody. You can lose to a team from the second, third or fourth division if you are not ready 100 per cent.

“We have to show our football, to push the game in the way we think will be better than them.

“I think we have got our chance and it’s a big challenge, a huge challenge, but we have to strive for this.”

Pellegrino is set to make a late call on whether Virgil van Dijk is ready to start his first game since January.

The Dutch defender was a late sub at Crystal Palace last weekend and put in another appearance for the under-23s on Monday having been out since the start of the year through a combination of injury and his transfer request.

It would be a big call to throw van Dijk back in to mark Romelu Lukaku, and though Pellegrino hinted at caution he admitted he hadn’t completely made up his mind yet.

He said: “We will decide, but every single week Virgil is important because he is getting better.

“After a long period of time without playing a game now he is training well, and it’s good news for us because we need Virgil like every single player in our squad.

“Virgil is an important player for us.

“I think every single week he will improve, but at the same time he needs to play, he needs to train.

“The best training session for me is to play games. Now he is playing in the reserves and 15 minutes is something and he is training well.”

Matt Targett is the only injury doubt for the United game after picking up a minor ankle knock.