The 23-year-old impressed during the summer's Under-21 European Championships and has been on the Cottagers' radar for the past year.
Good reports: Marcel Gecov (right)
Gecov has penned a two-year deal with the club after successfully passing a medical.
'He's signed and I am happy with him,' said Jol. 'He is a very talented midfield player and played against England [in the Under-21 European Championships] and got two assists so he is full of confidence.
'He knows he can play against English teams and that helps. He signed the contract yesterday.
'He had a very good tournament and was very decisive in games. That gave us confidence and he has been on our radar for at least a year.
'The Fulham scouts knew him and had very good reports on him.'
The deal is reportedly worth ?700,000 and Jol believes Gecov is a good addition to the Cottagers' squad.
'He is a typical midfield player and he is relatively young, he added.
'He is aggressive and, as I've said, I am happy he is on board.'
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