The Rebels host the Chiefs at AAMI Park on Friday night wanting the win to secure their first-ever play-off berth.
Currently eighth, a loss with a bonus point in the final round clash could also see them possibly sneak in.
Cooper, who won the Super Rugby title with Queensland in 2011, said the Rebels didn’t need to add anything to their game for the crunch encounter.
He said they just needed to bring their best rugby.
“For all the players to be able to be in the position that we’re in now, we’ve played some great football,” Cooper said.
“There’s been some times where we haven’t played the best football but we’ve put ourselves in a position to hold our destiny in our own hands.
“That’s what I’ve been saying to the boys – just continue to believe in yourself, believe in the team and what we’re doing and we’ll come out and get the right result.”
One area he conceded required attention was their defence after a rampant Crusaders outfit posted 66 points in a humiliating defeat last round.
The Chiefs have plenty of potency in that department, upsetting the Crusaders in their recent clash in Fiji.
“Every team has to tighten up their defence going into playoffs and the Chiefs are a great attacking team but so are we,” Cooper said.
“I think for me it’s not so much focusing on slowing them down, it’s just us being our best and when we’re at our best we’re going to be very hard to stop.”
Cooper only played the final 10 minutes of the Crusaders loss while his halves partner, Test halfback Will Genia, sat out under the Wallabies rest policy.
Both players could be playing their last games in the Rebels strip, although they indicated they would like to re-sign if a deal could be done.
Cooper said he didn’t want to think about contract negotiations.
“I’ve loved my time here in Melbourne but I just want to focus on beating the Chiefs.”
They can also potentially make the top eight finals with a win.
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