The Red Devils manager signed the Spanish full-back from the Reds during his time at the Bernabeu.
Arbeloa, speaking to Spanish newspaper AS, heaped praise on the Portuguese and insists he will be pleased with his first year in charge at Old Trafford.
“I think the bravest person I’ve met in football is Mourinho. He has to be happy with the year he’s had at [Manchester] United,” Arbeloa told AS.
Now retired, the 34-year-old admits regret in the way he hung up his boots after a year with West Ham back in the Premier League.
“I’m not retiring from football in the manner I’d have liked to,” Arbeloa admitted.
“I’d have liked to hang up my boots in the way Xabi Alonso did, for example.”