Stormers out to destroy hapless Kings
The Cape side are back home after a successful Australian tour where they thumped the Melbourne Rebels 57-31 before beating the Western Force 22-3 last weekend.
"What we learnt from the past is that this week is more crucial than the quarterfinal week in terms our preparation," Fleck told reporters in Bellville on Tuesday.
"I think if we take our foot off the peddle this week we are not going to do well next week.
He added: "Momentum is everything for us - we need to find an intensity that we have not had this season and that is what we need to take into this game. It is actually an extremely crucial week and game.
"Next week there is going to be a lot of focus and pressure on the squad, but it is all about us relieving that pressure and focussing on us. We want to play at another level this weekend. We want to play at a different intensity that we haven't had this season yet and that has got to be our key focus for the week."
The Stormers dominated the Force and Rebels up front in the last two weeks and they will be looking to their forwards again to lay the platform for victory against the Kings.
However, Fleck believes the Port Elizabeth outfit will provide them with a good test in that area of the game.
"There [Kings] set piece is good. We have been impressed with their line-out and their scrummaging work has been pretty good as well. They are not an easy side to play.
"It looks like they play with a lot of passion and they play for each other and that always makes them a dangerous side. We need to be at our best to beat them," said Fleck.
Meanwhile, co-captain Frans Malherbe could share the captaincy with Schalk Burger this weekend.
Malherbe still has to prove his fitness ahead of the game after being sidelined for the last two weeks with a neck injury.
Burger captained the side on their Australian tour.
"If he [Malherbe] is available for selection, he will be part of the captaincy.
"It is important that we develop that leadership group. Schalk Burger is not going to be here next year and we need guys to come through in the mix. Juan de Jongh is not available to us and Malherbe has done a phenomenal job as a captain for us.
"Burger stepped up to the plate. The team needed him as a leader and he did a phenomenal job on tour.
"Should Frans be available, he will be available in the captaincy role with Burger. If not, then Schalk will continue as sole captain of the team," Fleck added.
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