North Melbourne has dropped to eighth place on the ladder after a 32-point defeat against West Coast.
In a game where both sides were fighting for legitimacy, it was the Eagles who led from start to finish to claim their first win over a top-eight side this season, winning 16.8 (104) to 11.6 (72).
The Kangaroos have now lost five of their last six, all against top-eight opponents. They have slid from the top of the ladder after round 12 to eighth just four weeks later.
Luke Shuey and Matt Priddis led the way in the midfield with 31 contested possessions, 14 clearances and 17 tackles between them, while Andrew Gaff was damaging on the outside with 25 disposals and a goal.
Shannon Hurn's kicking out of defence was flawless, with all 16 of his kicks hitting the target, including a rare shot on goal. Jeremy McGovern took five contested marks in defence and was resolute throughout.
Josh Kennedy bagged four goals but could have claimed the lead in the Coleman Medal if he didn't miss four other chances.
Ben Brown was excellent up forward kicking four goals for North, including two freakish efforts, and Andrew Swallow fought hard with 25 disposals, 12 contested, in his 200th game. Trent Dumont was also a good contributor with 21 disposals and a goal.
Youngster Ryan Clarke showed plenty of promising signs on debut, finishing with 21 touches.
Eagles coach Adam Simpson said mid-week that the Eagles needed to at least match or better the Kangaroos in the contest if they were to win on Sunday, and they did just that with a fierce display around the ball.
They only lost the contested possession count by four and the clearances by five despite Todd Goldstein's 65 hit-outs. The Eagles laid 77 tackles to 60.
They were far more efficient going inside 50, yielding seven more scores from the same number of entries.
The Kangaroos did not help their own cause. West Coast kicked four goals courtesy of 50m penalties the Kangaroos gave up through either ill discipline or carelessness.
North's injury toll also continues to mount. They entered the clash without star trio Daniel Wells, Jarrad Waite and Shaun Higgins and then lost Nick Dal Santo pre-game due to illness.
Farren Ray suffered a hamstring injury in the second term and took no further part in the match, before Mason Wood left the field in the third term, giving the Kangaroos just two on the bench in the last quarter.
MEDICAL ROOM
West Coast: The Eagles appeared to escape without any injury issues.
North Melbourne: Dal Santo was withdrawn pre-game due to illness. Ray injured his right hamstring in the second term and did not return. Wood suffered when Will Schofield accidently fell across his leg.
NEXT UP
The Eagles will play at the MCG for just the second time this season when they face Carlton on Sunday. The Kangaroos face Port Adelaide off a six-day break at Etihad Stadium on Saturday.
WEST COAST 3.2 9.4 13.7 16.8 (104)
NORTH MELBOURNE 2.1 6.4 8.4 11.6 (72)
GOALS
West Coast: Kennedy 4, Cripps 3, LeCras 2, Gaff, Hurn, Lycett, Yeo, McGinnity, Darling, Masten
North Melbourne: Brown 4, Thomas 2, Gibson, Dumont, Goldstein, Wood, Anderson
BEST
West Coast: Shuey, Priddis, McGovern, Kennedy, Masten, LeCras
North Melbourne: Swallow, Ziebell, Brown, Gibson, Dumont,
INJURIES
West Coast: Nil
North Melbourne: Dal Santo (illness, replaced in the selected side), Ray (hamstring), Wood (left knee)
Reports: Nil
Umpires: Dalgleish, Nicholls, Kamolins
Official crowd: 35,168 at the Domain Stadium
