IT TOOK a three-quarter time Sam Mitchell "rocket" to launch West Coast's midfielders into action in Saturday night's come-from-behind win over Collingwood, Elliot Yeo says.

Trailing by 10 points at the last break, the Eagles kicked five goals to one in the final term to book a home preliminary final in a fortnight's time.

As coach Adam Simpson urged his side into action, it was Mitchell's spray that kickstarted Yeo and his midfield teammates.

“It was more Mitch, (he) 'got up' the mids and had a crack at us for certain things we weren't doing too well," Yeo told Channel Nine.

"He put the rocket up us, (but) Simmo (Adam Simpson) was the other way round.

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"He just backed us in, I guess he wanted to have every opportunity for us to win and halve every contest, try and get the ball forward and get it deep."

Mitchell's message had immediate effect, the Eagles winning the contested possession count 47-33 in the last quarter to overrun the Pies.

"That's the first time I've seen him (Mitchell) come down and have a fair rocket at the midfield group.

"It was something different and I guess the boys responded really well, which is a good sign."

Yeo (36 disposals, 24 contested) led the charge, while Jack Redden's career-best season continued with 32 touches.

Dom Sheed, dropped to the WAFL twice this season, picked up 15 contested possession among his 27 disposals.

The Eagles will meet the winner of Friday night's first semi-final between Hawthorn or Melbourne in the preliminary final, to be played on Saturday September 22 at Optus Stadium.