"In the first half (against the Blues) they tried to open it up a wee bit, and it didn't quite come off, so they tightened up. But we know travelling to South Africa that it is tough that first week, and then you settle into it, so we are expecting a big challenge on Saturday night."
Retallick is not reading too much into the Bulls poor one win-three loss start to the campaign after getting an old fashioned touch up from the South Africans pre-season in Brisbane.
"We played them before the tens in Australia, and they beat us that day, and that is definitely where they won the game. They scrummed and mauled us and played for penalties and kicked in the corners.
"That is their bread and butter, and they are physical, big boys so if we can't nullify their scrum and their maul it makes for a tough day.
"We have had some trouble conceding penalties in the last couple of games, so we need to get out discipline right so we don't give them any chances. It is a big focus for us to shut their ball down at lineout time so they can't get their maul set."
The Bulls have spent the week in Rotorua away from prying eyes getting themselves mentally and physically prepared to take on the unbeaten Chiefs who are four from four.
Retallick is pleased with the start but typically not getting too carried away.
"We have a good group here, and there is quite some excitement amongst us and some competition for places. We have worked hard to win those four games and to sit back in the bye week with 19 out of 20 possible points we are pretty happy.
"But it is a long season, and no one is going to remember who won the first four games.
We have to keep doing it week in, week out."
Last week's bye meant Retallick and his wife and daughter could spend some quality time in Melbourne after the Rebels game staying with his cousin and Bay of Plenty Steamers captain Culum Retallick for a few days.
The two love getting the chance to oppose each other and Brodie said it didn't take long for Culum to make his mark.
"It is always nice, and he got me in a bit of a head high, and he said 'I had to get you once'. There is always a little bit of banter going on. It is good to see him playing well for (the Rebels)."