PREVIEW By North-west correspondent Alex Stevens

Jurgen Klopp is set to ring the changes once again as he restores the big hitters for Liverpool’s first European semi-final in six years.

The German manager made five changes against Newcastle at the weekend following a thumping 4-0 win over Everton and a weakened team responded with a 2-2 draw.

The big decisions for Klopp ahead of the trip to Villarreal for the first-leg of the Europa League last-four clash are who should partner Dejan Lovren at centre-back and the identity of his central midfielders.

Kolo Toure, Lucas Leiva and Martin Skrtel are the three players in contention to play at centre-back, with the experienced Slovakian appearing the most unlikely after playing just 135 minutes since December and struggling for form since his recovery from a hamstring injury.

Lucas was on the bench for the Newcastle match, which suggested the veteran will start in Spain, either as the midfield anchorman or in a centre-back position in which he has looked very comfortable during a number of matches this season.

If Lucas partners Lovren, Joe Allen will almost certainly start in central midfield and given the chance to continue the excellent impression he has made in recent months.

In recent month, the Merseysiders have produced their best football since Luis Suarez was at the club, scoring 18 goals in their last five matches.

At the heart of the free scoring has been the quick interplay of Philippe Coutinho, Roberto Firmino and Adam Lallana, while Daniel Sturridge has struck in four consecutive league matches.

The attacking quartet are all expected to start for a team weakened by the unavailability of four players who would have expected to be in the line-up.

With Divock Origi, Jordan Henderson and Emre Can all out injured and facing uphill battles to play again this season, and Mamadou Sakho not selected after facing a drugs test, youngsters Cameron Brannagan, Sheyi Ojo and Pedro Chirivella have flown to Spain as part of the 20-man squad along with fit-again Christian Benteke.

Liverpool (possible): Mignolet; Clyne, Lucas, Lovren, Moreno; Allen, Milner; Lallana, Firmino, Coutinho; Sturridge.

In other Liverpool team news, the Merseysiders have been given a fitness update on another big-name attacker.