Le Havre could not recover after falling behind on goals by Tony Kociszewski and Julien Perrault in the first 38 minutes before 1,400 fans at the Gaston Bonnet Stadium.
Le Havre had won four straight games under interim coach Christophe Revault to advance to fourth place in Ligue 2, three points out of the top three. Bradley will make his Ligue 2 Nov. 23 when it hosts Brest.
The coaching change marked the third time in four years Le Havre made a change in the first half of the season. Thierry Goudet had been hired last December but was fired in late September after Le Havre win one game during a period of seven games.