Paolo Di Canio will "galvanise" Sunderland, according to the man who gave the controversial Italian his first chance in management.
Former Swindon chairman Jeremy Wray also described David Miliband's decision to quit his posts with Sunderland in response to Di Canio's appointment as a "sad knee-jerk response".
Former foreign secretary Miliband immediately resigned as Sunderland's vice-chairman and non-executive director after Di Canio was named Martin O'Neill's successor last night, citing the Italian's "past political statements".
Di Canio has admitted to having fascist leanings, telling Italian news agency ANSA in 2005: "I am a fascist, not a racist."
Wray, who appointed the 44-year-old as Town boss in May 2011, does not think the outspoken views will conflict with Di Canio's attempts to keep Sunderland in the Barclays Premier League.
He told BBC Radio Five: "It is a sad knee-jerk response. I doubt David Miliband has ever met Paolo Di Canio. I've known him for two years. I don't think politics was ever discussed once.
"Paolo will have many strong views. He probably has a strong view on whether Italy should be in the Euro, gay marriage or the endangered Siberian tiger, but I doubt if it's really relevant to keeping Sunderland in the Premiership.
"I think anybody's political views and their private views - as long they're private and how they conduct themselves away from their job - are pretty irrelevant.
"Nothing of that was ever discussed during his time at Swindon. He was focused full on 24 hours on success for us and that's what he'll do for Sunderland."
Sunderland dismissed O'Neill on Saturday evening following the club's 1-0 home defeat against league leaders Manchester United.
That result left the Black Cats without a win in eight games and just a point clear of the relegation zone.
With seven games remaining, Di Canio faces a fight to keep Sunderland in the top flight but Wray believes the former West Ham, Lazio and Celtic striker will be a roaring success on Wearside.
"He will galvanise the team. He is passionate; he eats, sleeps and drinks it. He is full on 24 hours a day and will be focused on the last seven games of the season.
"The Sunderland fans who are nervous now and are doubting the appointment should have no fears and trust what I saw in him is what (Sunderland chairman) Ellis Short will have seen in him as someone who is committed to the job."
Wray added: "There was no doubt that when he was at Swindon he was cutting his teeth in management, but I can assure you I think he's ready for the step up.
"He's learnt a lot, he's very intelligent, he's a quick learner and he's his own biggest critic.
"He'll have seen where he's gone wrong in the past and I think it's a really astute appointment."