CHRIS Fagan said it was Greater Western Sydney's "ferocity" that won it Saturday's game against Brisbane, but in reality, the primary factor was the Lions' horrible kicking at goal.

A simple look at the scores – 13.4 to 8.16 – shows how the home team missed a gilt-edged opportunity to solidify second spot on the ladder, and a deeper dive illustrates just how unlikely the outcome was.

According to Champion Data's 'expected score' statistic, Brisbane should have won by 41 points based on where the respective teams' shots at goal came from.

The Lions were projected to win 100-59. As the saying goes though, bad kicking is bad footy.

It started with their first set shot when Joe Daniher hooked one from 30m out just to left of centre.

It was contagious. 

Cam Rayner missed from 35m directly in front. Will Ashcroft hit the post from 10m with a left-foot snap, Daniher missed everything from 20m. That was in the first quarter when Brisbane led by 30 points despite generating 13 shots at goal to one.

Late in the third term, and holding an 18-point lead, Charlie Cameron missed from 25m bang in front, while it was Logan Morris' turn early in the last from slightly further out.

Brisbane scoring 36 points below their expected score is the second worst result of any side this season. 

The 59-point swing (Brisbane expected to win by 41 and losing by 18) is the equal biggest swing in any match over the past five seasons.

The Giants were ruthless.

They converted at 72 per cent accuracy, compared to Brisbane's 29 per cent, continuing a trend that has seen them ranked first in the competition since round 16 (62 per cent).

Darcy Jones' two running goals in the final term were fantastic, while Aaron Cadman's third to ice the game was a wonderful set shot from 45m on a difficult angle.

With a cumulative 'score over expected score' of plus-129 for the season, the Giants are third in the competition, while the Lions' are 13th with a minus-55 tally.