While their opponents felt they wasted their chances, both defences held firm as their opponents attacked late and hard.
Much of it had to do with defenders working together to allow teammates to take intercept marks.
Not only do intercept marks point to the skill of players, they also suggest good starting positions and players making quicker decisions to read cues up the ground and move into defensive mode.
It also alleviates pressure for defenders, removing the possibility of one conceding a free kick at ground level or a small forward crumbing a goal.
And it allows a counter attack to start.
Essendon's Dustin Fletcher, who has built a career on his ability to read cues and intercept opposition attacks, is the benchmark when it comes to defensive intercepts.
Funnily enough Fletcher didn't take a mark inside the defensive 50 during Saturday's game but he ran interference throughout the final quarter as Essendon repelled Bulldogs' attacks.
Cale Hooker – as he often does – did the job in the air.
Fletcher's positioning either forced the Bulldogs to kick long or to make a second decision. It meant they bombed the ball repeatedly in the last quarter to positions where Essendon was able to outnumber them.
The evergreen Fletcher is in the top 10 average rebounds from the defensive 50 (average of five) and managed to rebound seven times at the weekend.
That's a good effort because the Bombers have conceded the fewest inside 50s during 2014 (averaging 42.9 conceded).
Melbourne relied on less renowned names to do its work.
Although it was no surprise Jeremy Howe took two intercept marks inside the defensive 50, Jack Grimes, Neville Jetta and Bernie Vince also chipped in with two marks each inside Adelaide's forward 50.
Rohan Bail, Lynden Dunn, Grimes and Howe also rebounded about one third of Adelaide's forays forward, with Grimes, Howe and Jetta recording disposal efficiencies above 80 percent.
Melbourne's defensive numbers are improving.
On average, the Demons have conceded 10 fewer goals and 10 fewer scoring shots per match in the first seven rounds this season compared to last.
Only nine teams have had fewer points scored against, and Melbourne has only conceded one more point than Essendon.
Melbourne has been in front during the final quarter of three games and been in every contest this year except its round two loss to West Coast.
Admittedly opposition clubs have kicked inaccurately against Melbourne, as only four clubs have conceded more scoring shots than the Demons, with Melbourne's opponents kicking an amazing 106 behinds from 180 scoring shots.
Not all of that is due to luck.
It's harder to kick goals when the opposition puts some scoreboard pressure on, as Melbourne has from time to time this season. Pressure on the ball carrier and forcing forwards wide also play a part.
Given Melbourne has the lowest inside 50s average in the AFL (41.7 inside 50s per game), with the second worst differential of 11.4 per game, its back six have done well.
The team has settled, with an unchanged line-up going into the Adelaide contest an unusual occurrence at Melbourne.
It was a sign that Paul Roos (who was a handy intercept mark in his playing days too) can hold his nerve - he didn't rush back Col Garland from an ankle injury and kept James Frawley in attack on Saturday, even though the temptation to return to the past must have been large.
On Saturday both Melbourne under Roos and Essendon under Thompson showed what a difference good defences make.