THE AFL will again trial four field umpires over the bye rounds.

It comes after the League successfully used four umpires during the bye rounds last year.

The use of an additional umpire was also experimented with in the last four rounds of 2015 and also in several pre-season matches.

With six games to be played in rounds 11 and 13 and seven games in round 12, more umpires will be available to adjudicate matches.

There will be seven games in round 12 because Port Adelaide and Gold Coast had a bye in round nine after playing China the week before.

Umpires coach Hayden Kennedy said the AFL wanted to have another look at how an extra on-field official could impact a match in the season proper.