The 25-year-old is the league's leading points scorer with more than 30 points in each of his last 11 games.
The reigning MVP told ESPN: "Individually, he can't be stopped by any one-on-one player. There's nobody that can guard him one-on-one.
"I like going against the best, and he's definitely right up there. He's a great guy to compete against, man. I wish I could play against him every night because he brings that competitive nature out of you."
James's Miami Heat face the Thunder later today.