"Middlesbrough have taken serious steps to get me, in that they've contacted my agent, and that is something that I'll study. There is already a Frenchman there and someone else that speaks French - no, there are two French players there - and apparently the manager wants to build a big team next season."
Perhaps Sebastien knows something we don't - after all, who will be the Boro boss next season? With Terry Venables still to decide whether he will take the top job at the Riverside, that question remains unanswered.
What seems sure, however, is that Sebastien has played his last, or at least penultimate, game for the Hammers.
"My priority is West Ham but the problem is that there are two clubs in England willing to pay 15 million (French francs - around £1.5 million pounds) for me. And I have a rendezvous with the Metz directors and a French club this week.
"I'll have to weigh up all the pros and cons but as I have always said my first choice would be West Ham."
With Trevor Sinclair likely, bar any hitches, to be fit for the start of the season, Sebastien's chances were likely to have been limited anyway next season, but at the right price he could still have represented a sensible investment at the right price.
It is a shame for the likeable Sebastien, whose enthusiasm for the club, if not extending to knowing whom Sir Geoff Hurst was when he walked past during the interview, is nonetheless obvious.
His delight at being involved in the win last weekend, which assured West Ham Premiership status next season, was obvious. He says: "I think we showed what we could do in the second half."
"That was so important because we had to show what we could do in front of our own supporters and finish well for fans who expect nothing less.
"I think we responded favourably to their concerns and the fact that we won 3-0 is thanks to them.
"Southampton are a good team and there was always that worry that we wouldn't do well in the last game. But, thanks to the talents of certain players, we got the 3-0 win which we deserved.
"It is unimaginable that we were still an hour and a half from possibly going down, but we always try to play the right way.
"In our heads it was always impossible we would go down and we played 'serenely' on Saturday. It shows that we merited a higher place in the table."
So, wherever Sebastien ends up, it is "bon chance" to the player who became part of Hammers folklore when he played his part in the FA Cup win at Manchester United.
"If I play my best next season I think I can become one of the best right backs in England," he insists. "I have a big heart and I want to graft, whether at West Ham or elsewhere.
"I will be signed for someone by the end of next week."