Shares in Juventus plunged as much as a quarter in value on Wednesday after the Italian soccer club was knocked out of Europe's Champions League competition by Ajax Amsterdam.
The Turin-based club lost 1-2 at home against Dutch club Ajax on Tuesday in the second leg of the quarter finals, resulting in a 2-3 aggregate defeat.
At 0730 GMT, Juventus shares were down 17.3 per cent at 1.3960 euros, after trading as low as 1.275 euros.
Juventus signed Portuguese star Cristiano Ronaldo for a transfer fee of 100 million euros ($A157 million) in the hope he would help the club win Europe's elite soccer competition, as he did with Real Madrid for the last three seasons.
Juventus have won the Italian league title seven times in a row, but have never managed to win the "treble" of the domestic league, Italy's cup competition and the Champions League.
Inter Milan are the only Italian club to have achieved such a feat, under coach Jose Mourinho in the 2009/2010 season.
Juventus, who have already been knocked out of the domestic cup competition this season, missed the chance to clinch an eighth consecutive Serie A title on Saturday after a surprise 2-1 defeat at SPAL.