The powerful defender was at fault for two of Fulham's goals in the Premier League clash on Monday, but he took to Twitter to apologise for his display.
"My first impression was he's got a lot of guts to apologise. He wasn't hiding. He apologised to the fans about his performance and the team's performance," Marsh told BBC Sport.
However, the former Blackburn Rovers centre-back was then forced to defend his high wages following a torrent of abuse.