HAWTHORN wingman Isaac Smith will have to pass a Thursday afternoon fitness test in Perth to be selected for the blockbuster qualifying final clash with West Coast.

Hawks coach Alastair Clarkson said the club had been "really surprised" by Smith's recovery from a medial ligament injury in his left knee, which he sustained in last Saturday's win over Carlton.

The pacy left-footer was deemed only a 50-50 chance of playing on Tuesday, but underwent a private fitness test on Wednesday before flying to Perth with an advance party of teammates, and remains in the mix to take on the Eagles.

"It will all be determined by how well he can move this afternoon when we have a run around, so if he's OK then we'll make a call right there and then, or if he's not," Clarkson said at Melbourne Airport.

"We need to win a game of footy so we're going to take our best team in, but we're not going to take in blokes that are not quite right.

"If he can't prove his fitness then he doesn't play, it's pretty simple really. We're taking a big group of players across there just as a contingency ready for him not playing."

Billy Hartung was among the Hawks who flew out on Thursday, with ruckmen Ben McEvoy and David Hale also boarding the plane west.

Fellow big man Jonathon Ceglar arrived in Perth as part of the advance group of six Hawks and looms as an inclusion to combat the athleticism of Nic Naitanui kick-starting the Eagles midfield.

The West Coast star and ruck partner Callum Sinclair were sidelined for the 14-point loss to Hawthorn in round 19, and Clarkson said winning the midfield battle would be crucial to put the clamps on the Eagles' potent forward line.

"(Naitanui's) part of that midfield that gives them really good supply, so we need to compete really well in that part of the ground. If he has a significant influence on the game it's going to make it really difficult for us to win," Clarkson said.

"I don't think that's any secret, he's quite possibly going to be the All Australian ruckman.

"We just need to compete right across the board – it's not just about Nic Nat.

"They've got a really, really strong midfield, a really, really astute defence with the way that they play, and their forwards, as I mentioned earlier, are probably among the most dangerous in the competition.

"So it's a significant challenge for us this week."

Clarkson said his side took confidence from beating the Eagles in Perth last month, which extended the Hawks' dominance to five straight against West Coast.

The Hawks are set to be bolstered by the inclusion of Cyril Rioli (illness), Luke Breust (rested) and Luke Hodge (suspension) on Friday night.

Meanwhile, Clarkson has been in contact to support Lance Franklin after it was revealed the ex-Hawks superstar would sit out the Sydney Swans' clash with Fremantle due to a mental illness battle.