Newcastle United must find £20 million to keep striker Michael Owen.

The Mirror says Toon want to protect their £16m investment as Owen's contract expires in June 2009 and the club do not want to lose him on a free transfer as early as January next year.

Owen will not accept a pay cut on his £5m plus-a-year salary and, to keep the No.10, United would have to compete with the length of contract Premier League rivals could offer.

Liverpool, Manchester City and West Ham will monitor developments.

A new deal for Owen would be a huge financial commitment for owner Mike Ashley, who will also fund Keegan's summer spree.

But it would leave open the option of recouping up to £10m from bidders if Owen stays fit and scores goals in the next couple of seasons.