LONDON • Mamadou Sakho's Liverpool future is in doubt after he was sent home from the club's pre-season tour of the United States by manager Jurgen Klopp.

The French defender was booked on the same flight to London from San Francisco on Monday as the defender Brad Smith, who is returning to England to undergo a medical before a proposed £6 million (S$10.65 million) transfer to Bournemouth.

Liverpool have confirmed Sakho will continue his rehabilitation from an achilles injury on his return to Melwood.

The former Paris Saint-Germain captain has not played any pre-season friendlies and is due to miss the start of the new Premier League season because of the problem.

However, his attitude around the training camp has caused concern for Klopp and is understood to be behind the decision to remove Sakho from the squad.

The £19 million defender has not played for Liverpool since April 20 after being accused of failing a drugs test by Uefa.

The case was eventually dismissed by Uefa's control, ethics and disciplinary body but cost Sakho a place in the Europa League final and the France squad for the European Championship on home soil.

Sakho is taking legal advice over Uefa's actions but a strained relationship with Klopp would raise doubts over his place at Liverpool.

Earlier on Monday, Stoke City confirmed the signing of Joe Allen from Liverpool.

The 26-year-old has signed a five-year contract after the clubs agreed a fee believed to be in the region of £13 million.

THE GUARDIAN