Fien has admitted the Dragons were under par during their 16-10 loss against rivals Cronulla on Monday.
And the former North Queensland hooker, who spent five seasons with the Warriors, is not expecting an easy ride when they cross the Tasman.
The Warriors are yet to record a victory so far this season, after crashing to defeats against Cronulla and Wests.
“New Zealand is not an easy place to go over and win footy games,” said Fien.
“The way they’ve started at the beginning of the season means they’ll be a desperate side – very much like how the Sharks were on Monday.
“As the game played-out and showed, the Sharks out-enthused us so we’ll have to bring a lot more intensity to the match.
“We’re very focused on what we have to do this week and its something we will have to get our heads around.
“We’re very confident in what we can do on the field but we have to get into the grind and show what we are capable of.”