Defoe pressed his claims by scoring the opening goal in England's 3-0 win over the Platinum Stars in their final warm-up game.
Only Wayne Rooney of the other front players did himself justice.
Defoe said: "I don't know if I've done enough. That's up to the manager.
"As a forward, scoring goals is the job you've got to do. If you can't do that, then you've got to work hard and look sharp.
"I've felt sharp in training, and from the training camp in Austria.
"I've always said you've just got to go out there, work hard and do your best and then leave it down to the manager.
"But, to be honest, it's all about the squad.
"In a major tournament, you need a squad, not just the lads who will start the game.
"It's important that even the lads who come on make a difference. You need that in a major tournament."