When West Coast have been challenged this season and found a way to respond, it has often been on the back of two of their most critical stars.

This duo hasn’t always fired together to get the Eagles out of a mess, but a lift from one has usually been enough to steady the reigning premiers and get the rest of the team back on track.

Captain Shannon Hurn and 2018 club champion Elliot Yeo have been West Coast’s escape artists in an up and down season.

So, with both sidelined against Sydney through injury on Sunday, perhaps it shouldn’t have come as such a surprise that the Eagles couldn’t find a response when needed.

Sunday’s loss was the Eagles’ fourth by 40 points or more this season, coming just after a 61-point win against the Western Bulldogs that had put them into the top four.

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They looked anything but a top four team on Sunday, and the absence of Yeo and Hurn was a big reason why.

Let’s start with Yeo. The games in which the bullocking midfielder has led West Coast out of a hole this season came against Adelaide in round 10, and Melbourne one week prior.

Against the Crows in enemy territory, Yeo was the grunt man with a massive 15 tackles, helping the midfield get back on top after falling 33 points behind as Luke Shuey and Andrew Gaff provided the finishing.

Camera Icon Sam Reid kicked three goals in the Swans’ big win. Credit: AAPIMAGE

It was a similar story one week earlier when his 16 tackles and 18 contested possessions laid the ground work for a fightback against the Demons.

Against the Swans on Sunday, no Eagle was able to pick up the ruthless tackling Yeo has made his trademark in recent weeks. The team was out-tackled 46-44, despite having 106 fewer disposals.

The loss of Yeo, who remains a ball-winning midfielder despite his tackling strength, was particularly felt by Shuey and Gaff against the most defensively-minded midfield in the competition.

With tagger Ryan Clarke making a beeline to Gaff, and George Hewett seeking out Shuey, the engine room was immediately blunted, with the Eagles’ pair combining for 10 possessions and one clearance in the first quarter.

Jack Redden was able to lift on the inside with six clearances for the match (season average 3.3) and nine tackles (5.2), but the Swans’ 17-11 centre clearances advantage was a factor that Yeo could have addressed.

Camera Icon Lance Franklin enjoyed his best game of the season with 5.4. Credit: AAPIMAGE

And what of Hurn’s absence? The games in which the skipper has lifted his team when they’ve been challenged came against the Dockers in round four and the Saints in round eight.

In a strange Western Derby, West Coast led from start to finish but looked shaky in the third quarter as Fremantle controlled the match.

While Gaff was brilliant on that day, it was because of Hurn’s steady hand in defence, with 32 possessions at 84 per cent efficiency, that the Eagles were able to stave off the Dockers’ challenge.

It was a similar story against St Kilda in round eight, with Hurn’s ability to marshal the defence a key to seeing off two runs from the Saints.

The Eagles’ backline was adrift against the Swans on Sunday.

Lance Franklin and Tom Papley each kicked five goals, with the Swans having 26 scoring shots from 46 inside 50s (the Eagles had 21 from 58 entries).

Hurns absence as a backline leader could be seen when Jeremy McGovern and Tom Cole got confused about who should run with Franklin as he led up the ground, allowing the champion forward to make uncontested.

It was also evident when Lewis Jetta turned inboard deep in defence and chipped a panicked kick to a dangerous spot, leading to a goal to Hewett.

Hurn’s direction and calming influence could have prevented such breakdowns in a defence that had only allowed two players to kick more than three goals this season (Brisbane’s Lincoln McCarthy and Geelong’s Gary Rohan).

The round 12 bye has come at a good time for West Coast. After seeing how much they miss their captain and club champion when they are both sidelined, they will be sweating on the pair’s fitness ahead of a Thursday night clash against Essendon.