Hollywood siren Megan Fox is struggling to save her marriage after her former co-star Shia LaBeouf claimed they had a fling while shooting for the Transformers films.

Fox, who met Brian Austin Green on the set of sitcom Hope & Faith when she was 18, married the actor in June last year.

LaBeouf made a comment recently about their fling that has left the couple "torn apart" according to a magazine report.

Reports have since emerged that former Beverly Hills 90210 star Green is positively fuming over Shia's claims, and that he has allegedly vowed to "punch Shia LaBeouf's lights out".