AFL Betting Tips 2025: Round 21 Best Bets And Betting Trends

It feels as if, for weeks now, little has changed in terms of the permutations for the quickly closing finals race of 2025.
There is still one win separating second-placed Adelaide from Fremantle in seventh, while Collingwood have lost their tight grip on first with two defeats from their last three games.
None of the top-eight sides can afford to take things easily heading into September, with the race for home ground advantage and the double chance wide open.
We can therefore invest in games involving finals contenders with confidence, knowing they have to give everything in the coming weeks, but a couple of other so-called “dead rubbers” have caught our eye from a wagering perspective.
Here are some of our best picks for Round 21 after looking at the hundreds of different markets offered by the best Australian betting apps.
AFL Round 21 Predictions:
- Sydney Vs Essendon: Under 149.5 Total Points - 1.90 With Picklebet
- Collingwood Vs Brisbane: Either Team To Win By Under 24.5 Points - 1.80 With Betr
- St Kilda -24.5 Points Vs North Melbourne - 1.90 With PlayUp
Sydney Vs Essendon, Saturday 4:15pm AEST
Our interest in this round begins at the SCG on Saturday afternoon, where AFL betting sites have set a notably low total points handicap, even for a Swans game.
That is because Sydney is in for a terribly wet start to the weekend, with the bureau on Thursday forecasting 10-45mm of rain across the city on Saturday, set to persist throughout the day and evening.
It should make for slippery and difficult conditions for two teams already in the bottom half of the table for scoring, with Sydney and Essendon averaging just 79 and 68 points respectively in 2025.
If rain drags that down even further, a total of under 150 points appears likely, especially with Essendon’s injury list stretching beyond a dozen players last weekend.
One man we nonetheless expect to contribute to the modest score is Sydney forward Isaac Heeney, who on five occasions this year has kicked multiple goals at the SCG (five twice and two three times), while his teammates have not done so more than three times each.
That is one reason why he is among the favourites in the goalkicking markets and is 1.65 with AFL betting apps to deliver again this weekend.
Best Bet: Sydney Vs Essendon: Under 149.5 Total Points - 1.90 With Picklebet
Player Prop: Isaac Heeney 2+ Goals - 1.65 With Bet365
Collingwood Vs Brisbane, Saturday 7:35pm AEST
Collingwood fans will be hoping the second Grand Final rematch of 2025 finishes anything like the previous one, when the Magpies travelled to the Gabba as $2.55 outsiders and came home with a 52-point victory.
Brisbane’s premiership credentials continue to be questioned on a regular basis, and they have slipped below Adelaide and Geelong in flag betting on betting sites courtesy of three defeats from their last four games against current top-eight sides, even if successive losses to GWS and Adelaide were down to poor kicking.
They were torn apart at the centre bounce by the Suns last week in a humiliating Q-Clash, so it will be interesting to see if Collingwood have learned from the Gold Coast’s approach.
Still, Brisbane rarely produce two consecutive poor games and are evenly matched with Collingwood this year across many key statistical areas such as clearances, marks inside both 50m arcs and tackles at both ends of the ground.
That, plus Brisbane’s seven-game winning streak in Victoria, is why we are anticipating a tighter showdown on this occasion and will be fence-sitting by taking a tri-bet market.
The Pies held Brisbane forward Logan Morris goalless earlier this year, but he has a strike rate of 56% for kicking 2+ goals this year, including both of his appearances at the MCG, so anything better than even money, and 2.07 looks to be good value.
Best Bet: Collingwood Vs Brisbane: Either Team To Win By Under 24.5 Points - 1.80 @ Betr
Player Prop: Logan Morris 2+ Goals - 2.07 With Unibet
St Kilda Vs North Melbourne, Sunday 1:40pm AEST
There is no doubt St Kilda got away with it last week.
Their all-time record-breaking comeback, in which they overturned the biggest three-quarter-time deficit in a victory, excuses the first three quarters of their performance to an extent, but it also shows what they are capable of.
The Saints have covered the pre-match line in each of their last five games and, if they can carry that momentum into this week, the -24.5 handicap set by Australian bookmakers could be well short of the final margin.
It is also worth noting that North Melbourne have one of the league’s worst records when it comes to covering the line, doing so in just 37% of matches.
It comes as no surprise that North are among the worst teams in the competition for conceding possessions, so we are expecting St Kilda’s Jack Macrae to have a busy week.
Macrae has hit 25+ disposals in 59% of games this year, including four of the five in which the Saints won, so a 25+ touch haul could marry up nicely with a handsome St Kilda victory.
Best Bet: St Kilda -24.5 Points Vs North Melbourne - 1.90 With PlayUp
Player Prop: Jack Macrae 25+ Disposals - 1.67 With Ladbrokes