During his two-year stint with the Cantabrian club, he played mainly with the reserves, but still contributed with 15 games (13 starts) in the 2004–05 season as the team narrowly avoided La Liga relegation.
In the 2008 summer he joined FC Luzern in the Swiss Super League, but left in the following transfer window, signing with OFI Crete in Greece.
Shortly before the end of the January transfer deadline, after an unassuming spell in Cyprus, Bertin returned to Greece, joining Veria F.C.
Bertin represented Haiti at the 2007 CONCACAF Gold Cup in the United States,[2] and made his debut in the nation's final group stage game, a 0–2 loss against Canada.
In February 2008 he played in a friendly with Venezuela, serving as warm-up for the 2010 FIFA World Cup qualifiers against the Netherlands Antilles, which ended with a 1–0 aggregate win – he appeared in the second leg, a 1–0 success in Willemstad – with Haiti thus progressing to the third round.