Keenly aware of the threat from former teammate Greg Inglis, Melbourne warn their strike weapon Billy Slater is getting back to his best for Friday night’s big NRL qualifying final clash with South Sydney.

The game’s two best fullbacks spearhead their teams’ attacks at ANZ Stadium, with Slater’s crown as No.1 under threat and the pair likely to have a huge say in which team gets a preliminary final spot and a week off.

Slater had a slow start to the season following a knee injury during last year’s State of Origin, while Inglis is finding form again after damaging his knee during this year’s Origin series.

But Melbourne skipper Cameron Smith is confident Slater is getting back to his elusive, exhilarating best.

“I think the last few weeks we’ve seen the best of Bill and that’s probably the best we’ve seen of him over the last 18 months – ever since he injured his knee,” Smith said.

“He looks like he’s running more freely.”

Slater’s statistics back up Smith’s words – nine tries and five try assists in his past seven matches.

The Storm are wary of Inglis’ ability to produce on the big occasion.

“GI is GI, he’s a big game player,” said Storm backrower Ryan Hoffman.

“He shows that in Origin, he showed that in finals for us for a very long time and he’s the one player that come finals he’s going to bring his A-game.”

While they have contrasting styles – Slater’s speed and agility against Inglis’ sheer power, the results are similarly devastating.

This season Slater has scored 17 tries to Inglis’ 14 and he averages 13.9 runs per game to Inglis’ 11.8.

But the giant Rabbitoh delivers an average of 152.3 run metres per game to Slater’s 135.5.

While Melbourne are often acclaimed as having the premier “spine” in the NRL, Souths have a challenger in Isaac Luke, Adam Reynolds, John Sutton and Inglis and

Hoffman said the Storm couldn’t afford to focus too much on Inglis.

“Souths’ spine is up there with the best in the game but it’s not one individual player,” said Hoffman.

“It’s them as a unit we’ve been spending a lot of time on because they’re not a one-player outfit.”

The Storm are keeping mum on who will start at five-eighth with Brett Finch and Gareth Widdop both training in the position on Thursday.

Finch has been under an injury cloud after damaging his sternoclavicular joint last weekend while England international Widdop is pressing to return after playing his first match since suffering a dislocated his hip in late June.

Hoffman believed Finch, as the incumbent, would start if fully fit.

“We’re not sure of the decision (coach) Craig’s (Bellamy) going to make,” he said. “They’re both fit and both raring to go.”