Former lightweight title challenger Nate Diaz is returning to the welterweight division and he will meet Matt Brown at UFC 189. 
The fight booking was made official on Wednesday evening.
UFC 189 will come from the MGM Grand Garden Arena and will be headlined by a title fight as Jose Aldo defends the featherweight title against Conor McGregor.
Diaz (17-10) has dropped three of his last four and is coming off a decision defeat in December against current lightweight champion Rafael dos Anjos. This will be his first fight at welterweight since 2011 when he lost to Rory MacDonald at UFC 129. Brown (19-13) will also enter this fight following a defeat as he lost a decision to Johny Hendricks last month and he has lost back to back fights. His last victory came in May of last year has he defeated Erick Silva by TKO.
The current UFC 189: Aldo vs. McGregor fight card is below.
Jose Aldo (25-1) vs. Conor McGregor (17-2)
Robbie Lawler (27-8) vs. Rory MacDonald (18-2)
Dennis Bermudez (14-4) vs. Jeremy Stephens (23-11)
Gunnar Nelson (13-1-1) vs. John Hathaway (17-2)
Brandon Thatch (11-2) vs. John Howard (27-11)
Mike Swick (15-5) vs. Alex Garcia (12-2)
Nate Diaz (17-10) vs. Matt Brown (19-13)