Romain Vincelot played for Poyet at Brighton - the club he took from the League One relegation zone to the Championship play-offs in the space of three-and-a-half years.
Poyet faces an even bigger salvage operation with the Black Cats, who are rock-bottom of the Barclays Premier League with just one point from their first seven matches.
But Vincelot told Press Association Sport: "He's in the kind of situation he was in when he arrived at Brighton, so I think he has the ability to do it.
"Then it is the Premier League, so it is a big challenge for him, but I think he has everything to do it properly.
"He's a really good manager and a good tactician, really unbelievable. He gave me good advice and lots of good habits on the pitch."
Poyet has signed a two-year contract on Wearside to replace Paolo di Canio following the controversial Italian's short yet turbulent reign.
The 45-year-old Uruguayan, who was sacked by Brighton for gross misconduct - an accusation he denies - in June, has his own reputation for being hot-headed.
Another ex-Seagulls player, former Spain international Vicente, branded Poyet "selfish" and "egocentric", but Vincelot never fell out with him despite dropping out of favour and eventually moving to Leyton Orient.
"I don't know about personal stories, for me there was no problem, and if there was an individual problem or a personal problem then I didn't know about it," added the French midfielder.
"He did such a great job and you have to make decisions. At the end of the day he was the manager and even if I was not having as many chances as I thought I deserved, the results spoke for him. When it is like that you can't say anything.
"He's passionate, like South Americans - or southern Europeans - can be, but it's not about your country.
"We have an English manager at Orient (Russell Slade) and when we don't do well here the manager looks like he comes from South America too! It's normal when you don't do well a manager goes a bit crazy. It's what players need sometimes."
Source: Sunderland-Mad
Source: FOOTYMAD
