The Premier League has said it hopes to start permanent concussion substitution trials from January, reports BBC Sport.

It follows football's lawmakers, the International Football Association Board (Ifab), approving trials in 2021.

The new rule means permanent substitutions can be made if a player suffers a head injury, even if all replacements have already been used.

To avoid potential abuse of the rule, opposition teams will also be able to make a change at the same time.

However, Premier League clubs have voted against the use of five substitutes for a third time, despite Ifab's confirming an extension to the rule on Wednesday.

Instead, the number of top-flight players allowed on the bench has increased from seven to nine.

This measure will come into effect from matchday 14, which begins on Saturday.