The event was headlined by a Featherweight Championship rematch between the current champion José Aldo, and top contender Chad Mendes. Their first fight at UFC 142, also contested in Rio de Janeiro, ended in a first round knockout victory in favor of Aldo.

The headliner was originally scheduled to take place on August 2, 2014 at UFC 176. However, on July 2, Aldo pulled out of the fight citing a neck injury suffered during training. Subsequent to Aldo's injury, that event was postponed on July 8, when the UFC announced they were unable to replace the original main event fight and with less than a month before the event, the decision was made to postpone the event – though the promotion said the numbering scheme for already scheduled pay-per-views after it, including UFC 177 in Sacramento on August 30, would remain in consecutive order. That entire fight card was re-booked for other events.

Jeremy Stephens was linked to a possible bout with Lucas Martins at the event. However, Stephens' manager indicated shortly after the fight announcement was leaked that they had no intention of taking the fight. Martins faced Darren Elkins instead.

Fabrício Camões was originally scheduled to face Josh Shockley at the event. However, Shockley was removed from the bout citing injury and was replaced by Tony Martin.

Alan Patrick was expected to face Beneil Dariush at this event. However, Patrick was forced to pull out due to a broken jaw he received during training. Dariush instead faced Carlos Diego Ferreira.

...
Wikipedia