Liverpool need at least three more signings during the summer transfer window if they're to compete with sides above them in the Premier League, according to former defender Phil Thompson. Dominic Solanke became the Reds' first signing last week but having finished 17 points behind eventual champions Chelsea further additions are required to ensure they can close the gap.

In his first summer window since taking over as manager Klopp spent just short of £70m prior to the 2016-17 season, according to Transfermarkt.com, with Sadio Mane's arrival from Southampton representing the Merseysiders' marquee signing. Yet, both Manchester City and Manchester United outspent the Anfield club and Klopp will be under pressure to match their rivals' spending power.

New chief executive Peter Moore has already pledged to support Klopp and sporting director Michael Edwards in the summer window and with Liverpool having the carrot of Champions League football to attract an improved cartel of player it is set to be a busy off-season for the club. And Thompson – a three-time European Cup winner with the club - feels a new core of the team is required.

"Liverpool need a stronger spine to the team, by which I mean a top centre-back, a strong holding midfielder and a striker who is ready to produce goals," he told Sky Sports. "I think they've made a terrific coup in bringing in Dominic Solanke, but he's not the answer because they need experience. They also need a left-back. James Milner has done a terrific job filling in but he's obviously not a natural left-back and is better in other positions.

Jurgen Klopp
Klopp has been urged to sign a series of key players to close the gap to champions Chelsea. Getty Images

"Offensively Liverpool can match most teams but they clearly need to improve at the back if they are to compete for the title, having conceded more goals than the three sides above them. Michael Keane and Virgil van Dijk are two I've mentioned before but there's going to be a lot of competition for them, although Mamadou Sakho would be a good bargaining tool after he impressed at Crystal Palace."

Van Dijk has been on Liverpool's radar for many months with the Netherlands international destined to leave Southampton in a deal which could be worth £60m, according to The Mirror. However, Saints have reported Klopp's side to the Premier League for making an illegal approach made to the 25-year-old.

Keane meanwhile is another player set to change clubs during the summer after excelling with Burnley last term. United have been heavily linked with bringing the England international back to Old Trafford two years on from him leaving the club during Louis van Gaal's tenure.