Rory MacDonald from Montreal, Que., salutes the crowd after defeating Tarec Saffiedine at UFC Fight Night 4 in HalifaxThe Canadian Press
Canadian Rory MacDonald will fight UFC welterweight champion (Ruthless) Robbie Lawler on July 11 in Las Vegas.
UFC president Dana White made the announcement at a Las Vegas news conference on the organization's plan to beef up drug testing.
MacDonald had been due to meet Hector Lombard, ranked sixth among welterweight contenders, at UFC 186 in Montreal in April.
But that fight was dropped after Lombard tested positive for steroids at UFC 182.
MacDonald (18-2) is ranked second among 170-pound contenders. The Montreal-based fighter lost a split decision to Lawler (25-10 with one no contest) when they met at UFC 167 in November 2013.
The MacDonald-Lawler fight will be the co-main event of UFC 189 at the MGM Grand Garden Arena. The previously announced main event pits featherweight champion Jose Aldo against rising Irish star (The Notorious) Conor McGregor.