"He changed a lot of things and moulded the teams into winning combinations," he said.
"He took them to another level, mentally. He's very tough mentally himself.
"But it's a challenge for the players and I can see them switching on this week - they're up against their old coach."
Ludeke, 33, a former Lions flanker, said his players were positive about the Carisbrook assignment.
"We've come here to get some points. We definitely think we've got a chance."
The Highlanders welcome back captain and flanker Taine Randell after a calf injury, and the team's confidence is soaring after their 45-4 thrashing of the Sharks at Carisbrook last Saturday.
- NZPA
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