The AFL has conceded a "technical error" during the GWS-St Kilda clash where 29 seconds was lost at the end of the second term.
The Saints kicked a goal with 34 seconds remaining on clock, leading by 32 points. However, the siren blew almost immediately as Tom De Koning and Jake Riccardi competed in the centre ball-up contest.
"Post a second-quarter goal by St Kilda player Max Hall, a technical issue caused the countdown clock to jump from 29 seconds to 00 seconds, effectively ending the quarter," a statement from the AFL read.
"Upon a full review, it has been determined that 29 seconds should have been added back onto the timeclock.
"In the moment, the timekeepers were unaware of the technical error. There is a manual backup process for the timekeepers to resort to, however in this instance that did not happen.
"Ahead of the next round of matches, the AFL will undertake re-testing of the relevant timekeeping technology and reinforce the manual backup process with all timekeepers.
"The GWS Giants and St Kilda football departments have been contacted today."
The error proved costly as the Giants ran out of time in a thrilling finish to Saturday's contest.
GWS kicked 7.8 to 3.4 in the second half, including a five-goal-to-one final term, but fell narrowly short by four points.
It wasn't the only timekeeping error during the match, as in the third quarter, the run-down clock jumped around from 9.41 to 12.46 before autocorrecting.
