This move was necessary because, as a British citizen, he would not have been allowed to join the French club due to the country's strict immigration rules.
However, with a Jamaican passport, Duffus is now free to sign with Saint-Etienne, despite the club already having filled its allowed non-EU spots.
The 20-year-old England U19 international has signed a four-year contract with the Ligue 2 team, which had also attracted interest from German clubs Bayer Leverkusen and Eintracht Frankfurt.
It remains to be seen whether Duffus will now commit to playing for Jamaica's national team in the future.
