Players have been warned that any attempt to stall or interfere with the play-the-ball rule will be penalised.

Super League clubs will also follow different substitution rules to Australia and the rest of the international game this season.

The Rugby Football League has decided to stick with the current system of six changes from four replacements but with unlimited use of the blood bin.

In the recent World Cup and the World Club Challenge between St Helens and Brisbane Broncos, teams were allowed to make up to 12 changes, including blood-bin substitutions.

The ruling will put Britain at odds with the Kangaroos in the autumn Ashes series.

Regarding the play-the-ball, RFL director of rugby Greg McCallum has identified key areas to be tightened up after a pre-season meeting with coaches.

Defenders will be penalised for:

• Flopping onto the tackled player or pushing them back to the ground
• Straddling tackled players as they attempt to regain their feet
• Pulling a tackled player's leg as he rises to play the ball
• Making any contact with the ball in the ball-carrier's hand
• Placing a hand on the ball-carrier's head or shoulder at play-the-ball
• Deliberately bumping or running into the ball-carrier at play-the-ball
• No team-mate of a tackled player may pull the tacklers off the player who is attempting to play-the-ball

Referees have been instructed not to delay a quickly-taken 20-metre restart and that the sounding of the hooter will instantly signal the end of the first and second halves.

Referees previously had discretion to allow play to continue if they felt the siren had been sounded during play.

Meanwhile, following a successful experiment in last year's World Cup, the League is introducing a system of match commissioners.

"If clubs want to raise an issue resulting from the game, the match commissioner will be the first person to contact," McCallum said.