The Pac Man and Bradley, 32, will meet on April 9 at the MGM Grand Garden in Las Vegas, the venue for their two previous encounters.
Bradley controversially beat the Filipino the first time out in 2012 but inflicted Bradley’s only loss as pro in the return 2014 fight.
37-year-old Pacquiao was expected to retire having been defeated by Floyd Mayweather in last May at the MGM and promoter Bob Arum was recently reported by Sky Sports as saying that he expected the Filipino to fight on.
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However, Pacquiao brought speculation to an end regarding his future, report Sky Sports News.
"I am retiring from boxing to concentrate on my political career," said Pacquiao.
"My fight with Timothy Bradley will be my last."
Pacquiao, an eight-weight champion, goes into his 66th and final fight with a record of 57 win (38 by KO), six losses and two draws.
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