2013 Lions: Wales link is reason Gatland chose Warburton
Sam Warburton's close relationship with coach Warren Gatland is why he was made Lions captain ahead of Brian O'Driscoll, says Martyn Williams.
Warburton was understudy to ex-Lion Williams at the Blues and Wales before taking over both number seven shirts.
Williams said Warburton has "a great relationship with Gats and I think that is probably why Warren's gone for him".
"He knows exactly what the game plan is, what the coaches want out of the team."
Warburton was named by Gatland on 30 April as the man to lead the British and Irish tourists to face Australia this summer.
On their time together at Blues, Williams said: "If you'd told me then [Warburton would lead the Lions] I would have been surprised.
"To be given the honour of captaincy at such a young age, it's a fantastic accolade, and he deserves it as well."
Gatland, who is on a sabbatical from his job as head coach of Wales, made 24-year-old Warburton Wales captain ahead of the World Cup in 2011.
His selection for Lions captain was seen as a surprise in some quarters because of Warburton's relative inexperience and the fact he did not lead Wales in the latter stages of the 2013 Six Nations.
Williams, who made his 100th and last appearance for Wales against the Barbarians in June 2012, added: "It's going to be tough because it's his first tour and I think for the first few weeks it's going to be difficult [for him] to take it all in.
"But he's got great men around him in O'Driscoll and [Paul] O'Connell [and] Gethin Jenkins... to guide him, and I'm sure he'll do a great job.
"He does his talking on the pitch, he's not going to be making any great speeches before or after games - he's a leader."
Gatland has been reported as saying one of the key reasons for his decision to go for Warburton as captain was the way the player deals with referees during matches.
Former Wales captain Jonathan Davies says that is a facet of the game which could prove vital during the three-match series against the Wallabies.