An undisclosed injury has forced Josh Samman to pull out of his fight with Uriah Hall on August 17th in Boston and replacing him in the fight will be John Howard. 
The Boston Herald reported the change on Wednesday and the UFC has now confirmed the report.
UFC Fight Night: Shogun vs. Sonnen will take place from the TD Garden in Boston on August 17th and will be headlined by a light heavyweight bout as former UFC champion Mauricio “Shogun” Rua faces Chael Sonnen.
Howard (20-8) will be returning to the UFC in this bout and he has won six of his seven fights since being released by the UFC. His last five wins have come by TKO/KO and his last two wins have come by knockout in the first round.
Hall (7-3) was on the most recent season of The Ultimate Fighter and lost in the final to Kelvin Gastelum by split decision. It was his first defeat since losing to Costa Philippou in 2011 in the regional promotion, Ring of Combat. Prior to entering the UFC, he had won three fights in a row which included winning the Ring of Combat middleweight title.
The current UFC Fight Night: Shogun vs. Sonnen card is below:
Main Card: (Fox Sports 1 – 8 p.m. ET/5 p.m. PT)
Mauricio “Shogun” Rua (21-7) vs. Chael Sonnen (27-13-1)
Alistair Overeem (36-12, 1NC) vs. Travis Browne (14-1-1)
Urijah Faber (28-6) vs. Yuri Alcantara (28-4, 1NC)
Matt Brown (17-11) vs. Mike Pyle (25-8-1)
Uriah Hall (7-3) vs. John Howard (20-8)
Joe Lauzon (22-8) vs. Michael Johnson (12-8)
Preliminary Card: (Fox Sports 1 – 6:00 p.m. ET/3:00 p.m. PT)
Brad Pickett (23-7) vs. Michael McDonald (15-2)
Conor McGregor (13-2) vs. Max Holloway (7-2)
Mike Brown (26-8) vs. Steven Siler (22-10)
Diego Brandao (17-8) vs. Daniel Pineda (18-9)
Preliminary Card: (Facebook – 4:00 p.m. ET/1:30 p.m. PT)
Manny Gamburyan (14-8) vs. Cole Miller (19-7)
Ovince St-Preux (13-5) vs. Cody Donovan (8-2)
Ramsey Nijem (7-3) vs. James Vick (4-0)