THE AFL has blamed "human error" for another timekeeper mistake during Saturday night's clash between Geelong and Collingwood, which resulted in 109 seconds being mistakenly added to the third quarter.

The Pies scored one behind, while the Cats didn't score during the additional time that should not have been, after timekeepers mistakenly added on time rather than subtracting it following a clock malfunction.

It had minimal impact on the outcome of the game, which Geelong won by 54 points.

"With 3.36 remaining in the third quarter, at a boundary throw-in, the time clock was stopped by the timekeepers and did not restart for a short period of time," the AFL said in a statement on Monday.

"Once timekeepers were aware, a standard manual adjustment occurred. However, time was added to the clock when it should have been subtracted. This was a human error by the timekeepers, subsequently leading to the third quarter running 1.49min longer than it should have.

"The issue has been addressed internally, with both clubs informed of the error."

It's the second time the AFL has conceded a clock error during a match this season, after a crucial 29 seconds were lost from Greater Western Sydney's narrow four-point loss to St Kilda in round two.

A technical glitch with 29 seconds remaining in the first half saw the clock immediately jump to half-time, with timekeepers unaware of the issue at the time and with the League's back-up processes not occurring.