Sunderland boss Steve Bruce feels Anton Ferdinand has struggled to cope being in the shadow of big brother Rio Ferdinand, the Manchester United star.
Bruce was understood to be angry when Anton failed to shake off a hamstring injury before the start of last season.
Ex-Man United skipper Bruce said: "It's no secret we had a stand-up row but that's behind us now.
"There's no doubt about Anton's ability, it's just down to concentration. I think Rio is the real problem - there have been too many comparisons."
