The mouth-watering showdown between State of Origin adversaries Greg Inglis and Mark Gasnier is not the only "head-to-head" duel that is drawing attention in the lead-up to Sunday's clash between St George Illawarra and South Sydney at Wollongong's WIN Stadium.

It is also expected to be the last time that teams coached by Wayne Bennett and John Lang line up against each other.

Bennett and Lang go back a long way – to the early 1970s in fact – when they were both making their mark as players. Bennett was a long-striding winger or fullback with All Whites Toowoomba and Lang was a rising hooking talent with Brisbane's Eastern Suburbs.

Their first meeting dates back to the Bulimba Cup final of 1972 when Lang's Brisbane side trounced Bennett's Toowoomba outfit 55-2 at Lang Park. Bennett and Lang were part of history, playing in the last ever Bulimba Cup match which ended a 50-year tradition of triangular contests between Queensland's south-east strongholds of Brisbane, Toowoomba and Ipswich.

A teammate of Lang's was 22-year-old Brisbane Souths centre John Grant, who is better known today as the chairman of the game's Independent Commission.

Within weeks, Bennett, then 22, and Lang, 21, were selected for Queensland although it was another year before they appeared together for the Maroons. In 1973, they shared an ignominious distinction with their Queensland team-mates, playing in three interstate matches in which the Maroons were held to nil in every game.

Their association as coaches dates back to 1981 when Bennett was in his second season in charge of Brisbane Brothers (his coaching career began in 1976 when he was still playing) and Lang accepted his first coaching appointment with his old club Easts.

Lang enjoyed early success, winning a premiership in 1983, while Bennett had to wait until 1985 to win his one and only Brisbane club premiership with Souths Magpies. Bennett headed south in 1987 to link with the Canberra Raiders, while Lang, after a five-year hiatus in the mid-1980s, returned to coaching with Easts in 1990 and won a second Brisbane premiership in 1991.

Bennett had returned to Brisbane in 1988 to head up the Broncos and steered them to their first two titles in 1992 and 1993. The following season, Lang made the jump to the Winfield Cup with Cronulla and crossed paths with Bennett early in his first year with the Sharks. It was a humbling experience for Lang, whose team was thumped 34-2 at Brisbane's ANZ Stadium.

But the tables were turned in 1995 when Lang's Sharks returned to Brisbane to record a 36-22 victory. It was a similar story of see-sawing results for the next six seasons when a Broncos win would be countered by a victory to the Sharks. In 18 matches between Bennett's Broncos and Lang's Sharks between 1994 and 2001, the honours were shared nine wins each.

The game that mattered most was the Super League grand final of 1997 when Bennett's team of all stars proved far too strong before a crowd of 58,912 at ANZ Stadium (Brisbane), winning 26-8.

Lang moved from Cronulla to Penrith in 2002 and in nine meetings to 2006, Bennett's Broncos won five games to four. In that period, both coaches led their clubs to premierships; Lang breaking through for his first major title with the Panthers in 2003 and Bennett taking the Broncos to their sixth premiership in 2006.

It has only been over the past two seasons that Bennett's teams have enjoyed any dominance over Lang's. Bennett's Dragons have won all three matches over the Rabbitohs since Lang took charge in 2010.

On Sunday, Lang will get his final opportunity to redress the imbalance before retiring as a top grade coach.

As "old" Lang signs off, Wayne Bennett, the "Old Man River" of rugby league coaching, just keeps rolling along.