The young centre-back has been tipped for big things and Leeds have been linked with putting in an offer of €22m plus 20 per cent of any future sale.
RB Leipzig are also interested in Gvardiol, but it has been claimed that the defender is prepared to snub other clubs to stay at Dinamo Zagreb.
However, according to The Athletic, Leeds still believe that signing Gvardiol is possible.
The Whites want the defender and are convinced of his quality.
They believe that he can still be tempted to make the move to Elland Road before the transfer window slams shut in early October.
Dinamo Zagreb were recently knocked out of the Champions League qualifiers and selling Gvardiol would bring in welcome cash to boost their finances.
The player may need convincing that leaving Dinamo Zagreb at the age of just 18 is not a step too far too soon.