In this file photo taken on Nov 23, 2022, Old Trafford stadium, home ground of Manchester United football team, is pictured in Manchester, northern England. (PHOTO / AFP)

Shares of Manchester United PLC fell 13 percent on Monday after a report said the Glazer family was confident of securing an investment that would allow them to retain ownership of the British soccer club.

The family also expects the investment to help them double the value of the club over the next 10 years, ESPN reported, citing a source.

Manchester United declined to comment.

The English soccer club's stock fell to $18.91, its lowest since late November, when the Glazers had started weighing options including new investment or a potential sale for the 20-time English champions that they bought 17 years ago for 790 million pounds ($977.31 million).

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In this file photo dated Aug 8, 2017, A boy displays a Manchester United flag prior to the UEFA Super Cup football match between Real Madrid and Manchester United, at the Philip II Arena in Skopje. (PHOTO / AFP)

A small portion of the club's shares is listed on the New York Stock Exchange. The market capitalization was about $3.6 billion as of Friday's close.

Sky News reported on Saturday that US private equity firm Carlyle Group Inc was in talks about a "major" investment as the auction of the Premier League soccer club entered its final stages.

In March, Reuters reported that the son of former Qatar prime minister Jassim bin Jabr Al Thani had submitted an improved bid to buy the club. The founder of chemicals producer INEOS put in a bid for the club in February.

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Any sale of the club would likely exceed the biggest sports deal so far - the $5.2 billion including debt and investments paid for Chelsea - sources had told Reuters previously.