UFC 189: Mendes vs. McGregor was a mixed martial arts event held on July 11, 2015, at the MGM Grand Garden Arena in Las Vegas, Nevada.

[5] The event was expected to be headlined by a UFC Featherweight Championship bout between the then champion José Aldo and Conor McGregor.

He reaffirmed that Aldo had a "bruised rib and cartilage" and that the biggest problem was the weight cutting process being complicated by the injury.

[9] The co-main event featured a UFC Welterweight Championship bout between then champion Robbie Lawler and top contender Rory MacDonald.

However, in mid-May, the bout was made the main event of The Ultimate Fighter: American Top Team vs. Blackzilians Finale which took place a day later at the same venue.

[20] ^ Jeremy Stephens was fined 20 percent of his purse ($8,000) for failing to make the required weight for his fight with Dennis Bermudez.

Sinéad O'Connor sang "Foggy Dew" for McGregor and Aaron Lewis and his band played "Country Boy" for Mendes.