Porto president Nuno Pinto da Costa admits they turned down huge offers to keep hold of Joao Moutinho this season.
The Portugal international is back on the radar of Andre Villas-Boas' Tottenham ahead of the summer market.
"We, fortunately, have resisted and will only sell when we know that we have to do it. But there are millionaires who do not have money limitations. It's hard to resist.
"We had major proposals by Joao Moutinho and had to make an effort to hold onto him," revealed Pinto da Costa.