West Ham manager Sam Allardyce believes Tottenham star Gareth Bale is worth "£40-50 million" amid speculation the Welshman could be on the move in the summer.
Bale has been in sensational form of late and has six goals in his last five games for Spurs.
That run has not only helped Spurs up into 4th place in the Premier League and moved them into the last-16 of the Europa League, but also prompted rumours of a move to Real Madrid for the 23-year-old in the summer.
The Hammers will have the chance to get closely acquainted with Bale this evening when they play hosts to Spurs at Upton Park.
Bale starred in Tottenham's 3-1 over West Ham at White Hart Lane, rounding off the win in November with a fine goal after a Jermain Defoe brace.
Allardyce says that given his recent form, he wouldn't be surprised if Tottenham received a sizeable offer for their star man in the summer.
"The world of football outside of this country might decide his worth," he said.
"There might be somebody else from another country that decides he could be the man, so that would inflate the price a little more.
"I would have thought that Tottenham would want nothing less than £40-50million."
West Ham go into the game in need of a win that will keep them clear of the relegation dogfight.
The Hammers are six points clear of the bottom three in 13th, but a win tonight could lift them up into the top half of the table.
Allardyce says in order to achieve victory, his side must avoid focusing entirely on Bale and play their own game.
"The main thing for us on Monday night is to worry about ourselves," the former Bolton boss explained.
"We understand that Tottenham have got lots of fantastic players and they are a great team - but we're not bad ourselves.
"Everybody's talking about Gareth Bale because he's playing well and scoring goals. He's one of a number of players that we're going to try to have to shackle to get a good result.
"We've got to keep as close an eye on those players as we can but also go and do our stuff when we get the chance."