With Jason Robinson having a wealth of experience across both league and union, he had quite a challenge in whittling it down to a top five opponents.
5. Wendell Sailor
"I played against him in both league and at the Rugby World Cup. He was a big guy, really strong, great feet, and was one of those players who was always going to be handful. It was always tough for me to never bring down someone big, but he was fast as well."
4. Mal Meninga
"He was just hard to get hold of. The Aussie had a low centre of gravity and was really strong. One of the all-time greats of rugby league."
3. Darren Lockyer
"He was just a really good skilful player. When you look at players who consistently performed, he was always the best. He could create something out of nothing and he did plenty of times against me."
2. Martin Offiah
"He made world-class players look average. If you are going to bet your mortgage on putting a player through a gap to score from 100m then he's your man. He's got a statue and deservedly so."
1. Jonah Lomu
"He was built like a forward. When you play nearly seven years in rugby league and 10 in rugby union, but he was completely different. He didn't just traumatize players, he traumatized teams. He was about 18 stone, he could run as fast as any winger and he had a sidestep."