Captain John Terry revealed the high standards wanted by England head coach Fabio Capello and admitted: "You can't even have a bad training session."
Capello will highlight mistakes made by his players by pointing at them with the red beam from the DVD hand-set when showing re-runs of matches.
Terry concedes Capello's demands may put fringe players hoping to make an impact under pressure to instantly perform.
But his approach has paid dividends, with England already guaranteed a place in the 2010 World Cup finals before tonight's last qualifier with Belarus at Wembley.
Asked whether the players feel on trial, Terry said: "Most definitely. We all feel that. I genuinely mean that.
"Every day in training, if you have a bad session, the manager is on top of you - asking you if you're tired or what's wrong?
"You can't have a bad session, a bad game for your club - and for those players on the fringe, it's highlighted a little bit.
"The lads who have been in there have been playing really well - so those on the fringe know they have one chance, and if they don't take it they might be back on the bench.
"It maybe puts them under a little bit of pressure, but that drive that everyone is showing to fight for their place is a good hunger to have in the squad."
