Stoichkov believes Real Madrid have paid way over the odds for the Tottenham winger.
Stoichkov said: "If Bale is worth 100m, I would have been priceless."
The Bulgarian has also hit out at Bale himself after the Welshman refused to turn up for Tottenham training on Tuesday and Wednesday.
Stoichkov said: "Bale has shown a lack of respect toward his Tottenham team-mates by not showing up for training."
Speaking to Ondo Cero, the former left winger, went on to question the success rate of players from the Premier League in Spanish football.
He said: "No Englishman who came to Spanish football has ever succeeded."
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