Kyle Walker conceded he is still learning on the job as England's right-sided centre-back at the World Cup after coming in for criticism from Rio Ferdinand.
An attacking full-back by trade, Walker has largely impressed since switching to the position for the Three Lions' March friendlies against Netherlands and Italy.
But he gave away a penalty for Tunisia's equaliser in England's eventual 2-1 Group G win in Volgograd, with Ferdinand describing Walker's body positioning as "criminal".
"It's a new position for me, of course I'm still learning," the Manchester City defender told reporters.
"I've got great people next to me and the gaffer [Gareth Southgate] as well, who's watching coaching me and making sure I know certain tips in key areas when I'm playing in that position.
"He's entitled to his opinion. He wasn't playing the game, so that's it.
"It's not that I've never felt uncomfortable about it. As I've said before, it's new tools to my toolbox that I feel will improve my game.
"I don't get forward as much, which is a big part of my game. But I can use my pace in different areas to cover people.
"As long as I'm on the pitch and England are doing well, I'm completely fine with it."
Group G outsiders Panama are up next for England on the back of their 3-0 defeat to Belgium.
Walker believes lessons learned from their Euro 2016 humiliation against Iceland means any slip-ups should be avoided.
"I think we’ve learned a lot. The team has evolved massively from the Iceland game," he said.
"We proved that against Tunisia. The board went up [for injury time] and I didn't even realise. We just kept to our game plan. We didn't panic and we got the goal at the end of it.
"I think that shows the character that's in the team and the belief that we have in each other. Hopefully the same thing doesn't reoccur."