The Crusaders need to bring the right attitude if they are to avenge their earlier loss to the Chiefs in their Super Rugby rematch in Christchurch, veteran halfback Andy Ellis says.

The game on Friday night is almost a must-win for the seven-time champion Crusaders, who are eighth on the ladder after four wins and four loses.

Ellis was a late starter in the competition through his playing commitments in Japan and his re-introduction was from off the bench in the third-round clash with the Chiefs, who had a record 40-16 win in Hamilton.

“That was frustrating but it probably was a kick in the pants for us and got us refocused,” he said.

“We’ve made some good growth since then although we’re still a bit up and down.”

Ellis said the keys to victory over the Chiefs were intensity in attitude and defence for 80 minutes.

“We’ve got to give it everything because we know they will,” he said.

“It will come down to being smart on attack and making good decisions.”

Ellis, in his 10th Super Rugby season and with 132 matches behind him, said the Chiefs had no discernible weaknesses.

“They’re strong all round and have a driving maul now, which has been effective for them,” he said.

“A lot of their game is about trying to get that turnover ball, that fast, unstructured ball, so they attack breakdowns and put a lot of pressure on there.

“Their counter-attack is very good with Tom Marshall and James Lowe at the back.”

After a stunning 52-10 win over the Sharks in Durban, the Crusaders returned home only to surrender a 14-3 lead and lose 25-20 to the Highlanders in Christchurch last Saturday.

Ellis said they could not afford a repeat performance.

“We started well against the Highlanders and carried on some of the momentum from the week before, then just went flat for whatever reason.”