Jurgen Klopp admits that Barcelona and Real Madrid continue to pose a considerable threat to Liverpool when it comes to retaining the services of key men.
The Reds have seen their ranks raided by La Liga heavyweights in the past.
Luis Suarez and Philippe Coutinho are among the more recent stars to have traded life on Merseyside for that in Catalunya.
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Speculation in the present continues to suggest that proven performers at Anfield are interesting those at Camp Nou and Santiago Bernabeu.
Klopp has no intention of sanctioning sales, but concedes that it can be difficult for some players to shun the advances of global superpowers outside of England.