ultimobici said:Yates? Got a link or a retraction?
The now defunct Torhout-Werchter Classic 1989, as reported by Le Soir on 11 October 1989:
"Sean Yates, le coureur britannique, vainqueur du Tour de Belgique et du GP Eddy Merckx, a subi un contrôle antidopage qui s'est révélé positif à l'issue de la première demi-étape du Torhout-Werchter Classic disputée le 9 août dernier entre Geel et Verviers. Yates avait remporté l'étape avant de récidiver, l'après-midi, à Charleroi, endossant du coup le maillot de leader de l'épreuve."
Sean Yates, the British rider, winner of the Tour of Belgium and the GP Eddy Merckx, returned a positive test after the first split-stage of the Torhout-Werchter Classic between Geel and Verviers on 9th August on which he gained the leader's jersey.
[Source]
As I stated in my earlier post, the exact nature of the substance was rarely if ever reported at that time. Interestingly though, there's an exception here in the same column: Delgado's use of Probenecid at the previous year's Tour de France is expressly mentioned.