SHARROD Wellingham admits West Coast was unsure how it would perform in 2015 after suffering a raft of early-season injuries.

The Eagles' defence was hit hardest, with star key defender Eric Mackenzie rupturing an anterior cruciate ligament in a NAB Challenge game in late February, and fellow tall Mitch Brown suffering the same season-ending injury in the round one loss to the Western Bulldogs.

Eagles conquer MCG

The loss of Mackenzie and Brown left the Eagles' defence severely undermanned, but talls Will Schofield and Jeremy McGovern have risen to the challenge impressively, with help from their fellow defenders.

The Eagles' defence has stood up so well that they will enter their round 13 bye with a 9-3 record and a competition-high percentage of 153.5 that puts them second on the ladder (although the Sydney Swans are 9-2 and have a bye this round).

Asked whether he was surprised by his team's strong start to the year, Wellingham told AFL.com.au the Eagles were developing a belief that they could cover the loss of key players.

"To be honest we were probably a bit unsure of where we'd be with the injuries that we've copped," Wellingham said.

"But in saying that we've adjusted really well and we've got great confidence in our structures and game style and that's what we're relying on more so than personnel.

"We think that we've got the ability to just get the job done and that's pretty much what we're working on.

"It doesn't matter who's out there, it's just about making sure we get the job done while we're out there."

Richmond looked like it could expose the Eagles' defence on Friday night when it named a three-pronged forward line of Jack Riewoldt, Ben Griffiths and Tyrone Vickery.

But Schofield and McGovern, with help from the likes of Wellingham, Elliot Yeo, Shannon Hurn and Brad Sheppard, kept the Tiger trio to a combined total of four goals, an effort that played a key part in the Eagles' 20-point win.

Wellingham said the Eagles had been confident they could meet the Riewoldt-Griffiths-Vickery challenge despite their depleted tall stocks.

Head-high rule confusing

"With our defensive line we play more of a structure than a one-on-one situation, we try to manipulate it so that we can get help when the ball does come into those big guys," he said.

"Only one bloke can mark it at a time so that's probably what we try and work on.

"No matter how many talls they've got, we'll try and work it out."

Nonetheless, Wellingham praised the way Schofield and McGovern had stood up in the first half of this season.

"They've held up enormously," he said.

"'Schoey' has been amazing, he's gone from a dashing half-back to a key-position player – it's been awesome.

"'Gov', on the other hand, has come in and we knew that he's got that talent and he's shown it week in week out, which is really promising.

"He's still only [24] games into his career. He's reliable, and for a big bloke he's got awesome skills."