By Suhas BhatFollow @@suhasrbhat
By Suhas Bhat reporting from Manila
The Brazilian was participating at Rise to Power in Manila where he had been given a shot at the Interim Bantamweight title, following champion Soo Chul Kim's absence through injury.
He faced Japan's Okazaki with the 33-year-old actually participating in his first fight outside his home nation.
The fight proved to be something of a mismatch as Fernandes regularly took his opponent to the floor and dominated him with a powerful ground game.
Towards the middle of the first round, a rear-naked choke could have decided the fight in the Dream Bantamweight champion's favour but Okazaki held on for the bell to prolong the contest.
Fernandes' superior grappling ability was evident most clearly when he attempted a flying submission in the second round. And towards the end of the five minutes, the image of Okazaki trapped on the ground with Fernandes towering over him perfectly summarised the lopsided nature of the fight.
Clearly ruffled by the pace of Fernandes' attacks, Okazaki seemed to be running away from any sign of conflict in the third round.
He was trapped into a body lock in the fourth minute of that round as Fernandes went close to sealing the fight once more with a head and arm lock.
Okazaki only came close to causing trouble with a sweep in the final minute although he wasn't swift enough to cause any damage.
Not for the first time, Okazaki was then trapped near the cage in the fourth round and pinned to the floor by the AMC Pankration fighter. But Okazaki was determined to go the distance and survived a fourth rear-naked choke attempt by the South American.
Both men traded few blows in the final round and Okazaki gave a glimmer of hope to his fans when he trapped Fernandes in a headlock but failed in an attempt to pull guard.
The Nakanoshima man quickly got to his feet but was in trouble a short while later when Fernandes caught his left leg. With just ninety seconds left on the clock, Fernandes brought Okazaki to the ground one last time for a final rear-naked choke attempt but could not finish the fight via submission.
Nevertheless, Okazaki appeared resigned for defeat after the end of the fight and Fernandes even demonstrated his confidence by carrying out a few mock pushups on the mat as both waited for the final decision.
The judges duly awarded Fernandes a unanimous decision win allowing the Brazilian to unite the Dream and One FC Bantamweight titles with the 14th win of his highly successful MMA career.