Conor McGregor’s coach John Kavanagh believes the star’s “obsession” with boxing training cost him against Dustin Poirier. McGregor famously swapped the octagon for the ring to battle Floyd Mayweather in 2017. Despite losing that big-money match, the 32-year-old was targeting a second foray into the ring against another legend in Manny Pacquiao. That looked set...