The former Chelsea and Hamburg defender, who has announced his retirement from football, has never apologised for a high tackle in a clash between the Netherlands and Portugal
Khalid Boulahrouz continues to show little remorse for the dangerous foul he committed on Cristiano Ronaldo at the 2006 World Cup.
In a last 16 tie between the Netherlands and Portugal which would later be nicknamed 'The Battle of Nuremburg', Boulahrouz caught Ronaldo's thigh with a high challenge after just seven minutes.
The former Chelsea defender was shown a yellow card and Ronaldo was forced out of the game before half time, leaving the field in tears with a large gash on his right leg.
Portugal won the game - in which referee Valentin Ivanov set a tournament record for cards shown in a single match at a Fifa tournament with four reds and 16 yellows - thanks to a single Maniche goal.
Boulahrouz, who recently announced his retirement from football, has never apologised to Ronaldo for the foul, despite having the opportunity to do so at Euro 2012.
"I haven't spoken to Ronaldo about it since then, but I heard from Edwin van der Sar that he still had a scar one-and-a-half years later," Bouhlarouz told Helden Magazine.
"In 2012 I saw him at the Euros. Wesley Sneijder was talking to him in the hallway when we had to wait before training.
"Sneijder called me: 'Hey Boula!' and then 'Hey Cris, look your best friend!' Ronaldo's face said it all, ha. I didn't say sorry, it was water under the bridge at that moment."
Ronaldo was critical of both Boulahrouz and match official Ivanov after the game in 2006.
"Considering what happened, I don't think this official should referee any more games in the World Cup," he said.
"It was clearly an intentional foul to get me injured. It was a really nasty tackle, but this is part of football.
"I am used to getting kicked now but I am unhappy about that one."
- Goal