"John and Rio Ferdinand were two of our best players in the World Cup. For me, John Terry has been the best centre-back in the world for the last three or four years," said the Liverpool defender.
"I wouldn't have anyone ahead of him. Rio was great in the World Cup. I can't complain about that, they are world-class players and, hopefully, I can learn from them. It is just one of those things - that I am playing at the same time as Terry and Ferdinand - but I've won 30-odd caps and I don't know how many more I'll have before the end of my England career.
"Whatever era you play in, you are always going to have competition. We have some of the best players in the world.
"I will have to do a lot of work on the training ground because playing left-back at Liverpool is something I haven't done for a while. I played left back for one season and didn't do too badly.
"But it is more demanding. I played full-back at the World Cup and you could tell the difference. Physically, you have to get up and down the pitch. Centre-back is more of a mental thing."