It's official. The lid is well and truly off at Adelaide, as the Crows stand proudly on top of the AFL as the only remaining unbeaten side.

In a battle of the unbeatens, the Crows hosted Richmond at Adelaide Oval, and the Tigers managed to stay with them for precisely one quarter of football.

The visitors led by nine points, but then gave up an 85-point swing in the final three quarters to be overwhelmed by a rampant Adelaide side.

Crows scoring blitz to start 2017 R1 v GWS: 22.15 (147)

R1 v GWS: 22.15 (147) R2 v Hawthorn: 16.17 (113)

R2 v Hawthorn: 16.17 (113) R3 v Pt Adelaide: 15.10 (100)

R3 v Pt Adelaide: 15.10 (100) R4 v Essendon: 24.9 (153)

R4 v Essendon: 24.9 (153) R5 v Gold Coast: 23.15 (153)

R5 v Gold Coast: 23.15 (153) R6 v Richmond: 21.14 (140) * Average score: 134.33 points per game (first six rounds) **Average winning margin during that time: 50.8 points

This followed an upset at the MCG, where the other 5-0 team, Geelong, was beaten by a resurgent Collingwood.

There are no more counterarguments to be made, Don Pyke's men are — at least for the moment — the clear frontrunners for this year's flag.

The Crows are averaging 134 points a game in attack — overall they are 100 points clear of the next best team in Port Adelaide — and they also have the league's third-best defence.

Safe to say, there are not many chinks in Adelaide's armour right now.

Crows defence gives Tigers no openings

It all starts in defence, where Richmond gave Adelaide a torrid time in a tough opening quarter.

The Tigers kicked 6.3 to Adelaide's 5.0, and they were looking fiercer in attack early on.

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But after quarter-time the game changed, the Crows stepped up one or two gears, and Richmond was left behind.

In the final three quarters, Adelaide booted 16.14 to Richmond's 4.1.

One crucial element was the ability of Adelaide's defenders to hit their targets coming out of the back 50.

Curtley Hampton's disposal efficiency was only 57 per cent, but his team-mates were elite, led by Rory Laird and Daniel Talia whose disposal efficiency was 94 per cent.

Brodie Smith hit his targets 90 per cent of the time, while Luke Brown (88 per cent), Jake Kelly (85) and Kyle Hartigan (80) were also impressive.

When you can't force a mistake out of your opponents' back six, it's very hard to score. Just ask Richmond.

Jacobs cleans up in the ruck for the Crows

Richmond went into the game with confidence in the ruck thanks to the success of former Swan Toby Nankervis, who had been excellent in the opening five rounds.

Adelaide had Sam Jacobs at the bounces, a ruckman who had been beaten previously this season by Port Adelaide's Patrick Ryder, Essendon's Matthew Leuenberger and the Giants' Shane Mumford.

The Crows' confidence paid off, however, as Jacobs dominated his opponent.

He out-rucked Nankervis 50-38, but also racked up 26 valuable possessions, won three clearances, took nine marks and kicked a goal.

This dominance extended to the midfield, with the home side winning the clearances, the stoppages and contested possessions.

Forward spread helping Adelaide

It's not just Tex and Eddie Crows goalkicking list for 2017 Player Games Goals Eddie Betts 6 20 Taylor Walker 5 18 Tom Lynch 5 11 Charlie Cameron 6 8 Rory Sloane 6 8 Andy Otten 6 8 Rory Atkins 6 7 Riley Knight 5 6

Looking in from the outside, the two focal points of the Adelaide attack are livewire Eddie Betts and spearhead Taylor Walker.

It's not surprising that they lead the Crows' goalkicking charts after six rounds — and Walker led the way with a bag of five against the Tigers — but it's instructive to see who else is on the list.

Tom Lynch (11 goals) is also a solid marking target, but the range of Adelaide options is growing.

Charlie Cameron is steadily becoming a more vital cog in the Crows' attacking game, while Rory Sloane can be relied upon despite his relative lack of size to take a number of vital pack marks each game and kick big goals.

Against Richmond he bagged three, and was an important outlet when the two main men were covered.

The Crows had 13 different goalkickers against the Tigers, and while much of that could be put down to the home side's overall dominance, it has to be a satisfying situation for coach Pyke.

Rivals fall off, as Giants the main threat

The Giants' win over Western Bulldogs puts them in line as Adelaide's main challengers for flag favouritism. ( AAP: Lukas Coch )

When it comes to assessing the Crows' rivals, there are marks against all of the nearest challengers.

Richmond's strong start to 2017 was helped by an easy draw, and the Tigers badly failed their first big assignment.

The Cats have looked solid in the early part of the season, but their surprise 23-point loss to Collingwood backs up the argument that if you can stop Dangerfield and Selwood, you can stop Geelong.

The Giants — fresh from a stirring win over the defending premiers Western Bulldogs in Canberra — can now perhaps be viewed as Adelaide's strongest challengers.

GWS has beaten the Suns, North Melbourne, an improving Port Adelaide and the Dogs so far this year, although it has to be said that they were well beaten in round one by none other than the Crows.

Adelaide has the Kangaroos, the Demons, the Lions and Dockers in the next four weeks, and on current form few would doubt their ability to stretch their record to 10-0 by the end of May.

Of course, these are early days, and you want to be the premiers in September, not in April.

But right now the evidence says that if you want to win this year's AFL flag, you'll have to go through Adelaide to do it.