Arne Slot admitted his concern at Trent Alexander-Arnold limping out of Liverpool's 2-0 win against Aston Villa with a suspected hamstring injury after just 25 minutes, saying that it is "always serious if a player goes off in the first-half."

Goals from Darwin Núñez and Mohamed Salah sealed the win, which moved Liverpool five points clear at the top of the Premier League heading into the international break, but Alexander-Arnold's injury cast a shadow over the victory.

The England defender sat on the turf and signalled to the bench that he was in discomfort and, despite undergoing treatment for three minutes, left the pitch clutching his right hamstring before being replaced by substitute Conor Bradley.

And while Liverpool boss Slot stopped short of ruling Alexander-Arnold out of England's Nations League games against Greece and the Republic of Ireland next week, he said that the 26-year-old's reaction to the injury was "not a good sign."

"It's difficult to say how serious it is, but it's always serious if a player goes off in the first-half," Slot told reporters. "He asked for it -- it wasn't because he was tired, but he felt something.

"That's not a good sign, but it's always difficult so close after a game to say how it is. I would be surprised if he is OK for the national team at the end of this week, but hopefully he can be."

Liverpool have won 15 of 17 games under Slot since his appointment as successor to Jurgen Klopp this summer and they sit top of the Premier League and Champions League tables.

But with home games against Real Madrid and Manchester City within the space of five days to come after the international break, Slot warned that Liverpool must remain focused and expect their rivals to compete to catch them.

"Every game is a big week against strong teams in big competitions," he said. "But we hope we have many more of these weeks to come.

"If I look at the games that are ahead they are tough. It will be a tough season in general. Margins are small, we have a margin but it is small. Many challenges to come for us.

"It's a long season and we have to continue to be at the top of our games as City, Arsenal and Chelsea can win as many as we have.

"It is never going to be easy but will push as much as we can."