Why did Donegal keeper Shaun Patton have to return to play at halfway line against Derry?

So why did Donegal keeper Shaun Patton have to return to the pitch from the halfway line after being treated for injury in their Ulster SFC quarter-final win over Derry?

The Donegal stopper went down with a leg injury around the 23rd minute of the game and was soon requested to leave the field of play by referee David Gough.

When Patton then looked to re-enter the play from behind his goal, he was instructed - by referee Gough and by his team-mate Ryan McHugh - to make his way to the halfway line where he would be permitted to return to the action once there was a break in play.

This led to a brief passage of play where Donegal were down to 14 men and had no goalkeeper on the pitch as they defended a throw-in on their own 21-yard line.

The injury would eventually force Patton off the pitch for good, in the 55th minute. Back-up keeper Gavin Mulreany replaced Patton for the final 20 minutes of playing time.

A new rule in place this season means a player not seriously injured who requires treatment must be treated off the pitch and can only return at the halfway line during a break in play - and with the referee's permission.

A player being treated for a serious injury is permitted to remain on the field of play.

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