BRETT KIRK has long been the most highly-rated supposedly underrated player in the AFL. Having spent the best past of a decade attempting to donate vital organs for the greater good of the Sydney Swans, no one has been left in any doubt about his ability to inspire.

But when former Collingwood premiership skipper Tony Shaw suggests Kirk is now "head and shoulders above the rest" as the best captain in the competition, the opinion carries some weight.

Kirk and Shaw are different characters. Shaw had some handy bloodlines as the brother of another former Collingwood captain, Ray, and yapped like a terrier. Kirk is a more serene figure. However, in the early stages of his career Shaw was, like Kirk, underrated - even ridiculed - because he was slow and, to exhume a phrase from the game's once colourful lexicon, could not kick over a jam tin. And yet, at the vital moments when the pace of the game is raised, the physical pressure is intense and the need for clear heads and clean disposal becomes paramount, Shaw - like Kirk - excelled as both player and leader.

It was during such frantic moments in the final quarter of Sydney's 11-point victory over Port Adelaide on Saturday that it occurred to Shaw, who was doing special comments for Foxtel, that he was watching one of the game's great skippers - and great players - bend the game to his will. Just as Kirk had risen during vital stages during the 2005 and 2006 grand finals.

But Shaw suggests Kirk might have gone to an even higher level since then.

"I think there was always a feeling he lacked a bit of penetration [with his kicking and running]," Shaw says. "From what I've seen, he might have improved on that. You look at the split of his ball-winning on the weekend: 15 contested possessions and 15 uncontested. He's getting it both ways now [rather than just in packs]."

Shaw acknowledges that the recent retirements of Michael Voss, Nathan Buckley and James Hird has stripped the competition of some of its finest leaders. Yet he does not hesitate to list Kirk in that elite company.

"When a player doesn't have that super athletic ability of Voss or a Buckley, he might have other strengths as a leader," he says. "He might better understand how hard some other players around him have to battle to survive. When you don't have those attributes, it's a matter of knowing your limitation. You know what you can do and you do it every time."

Stuart Maxfield, the former Swans captain who helped establish the club's famed Bloods leadership group, and who has been a strong influence on his friend Kirk, agrees that it is possible the 31-year-old has grown further as both a player and leader.

"We were talking the other day about rookies who start out as taggers," says Maxfield, who now works in recruiting and the Swans' leadership program. "Brad Sewell (Hawthorn) and Kane Cornes (Port Adelaide) are a couple. They learn so much by playing on the best players every week and eventually they become ball magnets themselves.

"Chris Judd was saying the other day how as a leader, he just wanted to do important things at important stages of games. Brett does that all the time. You can't underestimate the influence he has on the culture of the place, the effect on the younger players like a Kieren Jack and Jarred Moore."

Maxfield says Kirk's involvement with the Dream Team in the recent exhibition game demonstrated his stature.

"You hear the comments coming back from people like [coach] Mark Williams about how he just naturally assumed a leadership role in that environment, which is pretty impressive."

Kirk is not the sole leader at Sydney, sharing the captaincy with Leo Barry and Craig Bolton. But Bolton takes no offence from the common suggestion that Kirk is the "spiritual leader" of the team.

"There's obviously no question he could captain this team by himself," says Bolton, who provides an assessment of Kirk that could come from Shaw's scrap book.

"As a player he has weaknesses that the opposition should be able to exploit," he says. "He's slow and he's not a long kick. But he's the most consistent player, the best leader, I've ever played with."