By Coral Barry

Jordan Henderson’s future at Liverpool has been plunged into fresh doubt as Jurgen Klopp prioritises the signing of a central midfielder this summer.

As revealed by Football Insider, the Merseysiders are closely monitoring Polish sensation Piotr Zielinski, while they also have an interest in Swiss star Granit Xhaka.

Speculation is intensifying that Klopp is considering offloading Liverpool captain Henderson in a bid to raise money for priority transfer targets.

The 25-year-old took over the armband from departed legend Steven Gerrard in the summer but has had his season disrupted by injury and poor form.

Zielinski, 21, has been one of the stand-out central midfielders in Serie A this season after establishing himself in the Empoli side while on loan from Udinese.

Borussia Monchengladbach’s Xhaka, 23, is also highly rated and the website of respected Italian journalist Gianluca di Marzio claims he is a priority target for the Merseysiders.

Both players thrive in the middle of the park and interest in the pair prompts fresh question marks over the future of Henderson, who currently occupies that role for Liverpool.

Amid suggestions of an impending Tottenham bid, Klopp refused to rule out a sale when he was asked on Sunday if he would ever consider selling the Merseyside captain.

“Everything is OK in this moment but nobody in the world, maybe only [Lionel] Messi, is unsellable,” said Klopp.

“I am pretty sure it is only a rumour [Tottenham wanting Henderson] but if not and if a player – let’s not say Hendo but any player – comes to me and says he doesn’t feel comfortable and wants to leave, style of play, more money, then you always have to start thinking.”

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A string of impressive performances and some stunning strikes last season in Gerrard’s absence earned Henderson the Liverpool captaincy.

However a foot injury in August last year sidelined Henderson until November and he has so far struggled to reignite his form.

Midfield partner, Emre Can has consistently outshone Henderson this campaign and it remains to be seen whether current coach Klopp has the same faith in the Englishman’s ability as the last manager Brendan Rodgers did.

In other Liverpool transfer news, the Merseysiders are targeting two full-backs in the summer window.