Complex sentence: Once again, Martinez fought for the PFC Lightweight Championship on January 17,2008 at "PFC 6" against Diego Saraiva and was defeated via submission due to a rear-naked choke in the first round.
Split into simpler sentences: Once again, Martinez fought for PFC lightweight title on January 17,2008 at "PFC 6" against Diego Saraiva. He lost via submission due to a rear-naked choke in the very first round.