The husband of Rachael Ostovich, UFC, arrested for attempted murder

UFC fighter Rachael OstovichThe MMA's fighter husband was arrested for murder several days after allegedly breaking his wife's face … and he is still behind bars in a Honolulu jail.

TMZ Sports broke the story … Ostovich – who was to withdraw from his appointment in January fight with Paige VanZant – was hospitalized this weekend with serious injuries – including a broken orbital bone – after her husband allegedly assaulted her during an argument at their home.

Police in Honolulu opened an investigation into domestic violence earlier this week … and the police are now telling us that 27 years have Arnold Berdon – Ostovich's husband and the father of his child – was arrested tonight on suspicion of attempted second degree murder.

Berdon – a fighter who owns a 7-2 record – is still in custody at the main PD station of Honolulu.

He has not yet appeared before a judge … where a bond could be fixed.

If he's released … Rachael's husband will not be allowed to contact Ostovich – because she has a Temporary restraint order against her husband … except contact.

A member of Arnold's family told us that he intended to vigorously challenge in court any allegation that he had assaulted his wife.

If found guilty, Berdon could face life imprisonment with the possibility of parole.

History in development …