FORMER Hawthorn great Shane Crawford says the Hawks will have failed to fulfill their promise they don't win the Grand Final.

Crawford believes the 2012 Hawks have more depth and better circumstances in their favour than the 2008 premiership side he was part of.

But he pointed to the side Hawthorn beat for that upset flag win as proof of what can go wrong if a champion side doesn't perform on the day.

"As we saw with Geelong in 2008, it doesn't always guarantee you success," Crawford said.

"You need to be right on the day, and you need a bit of luck on the day.

"Hawthorn have got some real star players, but it's the way they team together, and have a real team focus in everything they do."

Crawford said the Hawks go into Saturday's preliminary final against Adelaide needing to win to at least guarantee a "pass mark" for their season.

But he believes the $1.55 premiership favourites must win the flag to deliver on their promise following a superb home-and-away season.

"They couldn't be in a better position to have an assault on winning their next premiership," Crawford said.

"They are really set up to come out and play really well at the MCG in front of their home crowd and have a win, and possibly go through to a Grand Final.

"I'd be extremely disappointed if they didn't win this week, and didn't win the premiership."