Sometimes you go digging for gold and strike it rich and sometimes you just make a big hole.

The Western Bulldogs did the latter for most of Friday night at Etihad Stadium, the Dogs going goalless in the second half of a 13.12 (90) to 8.7 (55) loss to Collingwood.

The Bulldogs appeared to have struck upon a rich vein of their best, running, attacking football as they kicked five unanswered goals in the first quarter.

But after leading by 26 points early in the second term, Luke Beveridge’s side crumbled in the face of increased pressure from the Pies.

“Sometimes you go prospecting and you make some discoveries – our first quarter looked pretty good, there were some encouraging signs,” Beveridge said.

“And other times in your exploration you come up well short and you’ve got to move to new territory.

“Our method needs to be matched by energy, endurance, some speed, some execution and skill and it all fell apart after quarter-time.

“We feel like we can play a stronger four quarters than what we did tonight but the evidence of the last two weeks says otherwise.”

Coming off a loss to Adelaide where the Dogs managed just two goals in total, their inability to kick a single major in the second half was alarming.

While Beveridge was largely pleased with his back six, he promised some soul-searching after his underperforming side slipped to a 4-6 record.

“The ball came out of our forward half way too easily,” Beveridge said.

“It felt like for most of the game our back end held it together pretty well but backmen can’t defend those open plays.

“So the 12 (players) through the middle of the ground and forward of the ball just became complacent and as much as that’s disappointing and deflating at least we know what it is and we can fix it.

“We know we can’t do that and play to a level that we know we can. Credit to Collingwood (but) we’ve got some soul-searching to do pretty quickly.”

Key defender Zaine Cordy will be assessed during the week after leaving the match with a concussion in the second quarter.