Tottenham negotiated a 10 per cent sell on fee when they let Gylfi Sigurdsson join Swansea.
Sigurdsson is the subject of transfer interest from Everton, who have already seen a £45 million offer rejected.
Swansea are holding out for £50 million – which would see Tottenham receive £5 million.
Everton are deliberating whether or not to up their offer for the Iceland ace.
Swansea City’s Gylfi Sigurdsson
The £5 million will be gratefully received by Tottenham, who would never have imagined when they sold the midfielder that he could move three years later for the type of figure he is being valued at.
Nonetheless it shows smart planning from chairman Daniel Levy to have had such a clause inserted ‘in case’.
Swansea City’s Gylfi Sigurdsson scores
Sigurdsson is wanted by Everton, who are expecting to lose Ross Barkley this summer with the midfielder making clear he wants out.
Tottenham have been linked to Barkley but have not met the 23-year-old’s valuation and with him currently recovering from a groin injury, the situation could drag out to the deadline.
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