Tackling pressure, particularly in the forward line, has lifted noticeably at West Coast this season, with draftee Jack Darling a big contributor so far.
Sheppard said it had been a major focus of the Eagles' pre-season, with 2010 premier Collingwood setting the benchmark for the young side to aspire to.
"The defensive aspect of the game has definitely increased his year and it's become more of a priority," Sheppard told westcoasteagles.com.au.
"Having a defensive mindset and getting that part of the game right is helping our forward attacks and it's really breeding a lot of confidence through the group.
"We did a lot of tackling through the pre-season and a lot of grappling, so that's been a huge focus for us.
"Collingwood's at the pinnacle at this stage, so we're trying to get to that level. We're working towards it and if we keep improving on our defensive aspects, we'll match it with the best."
Sheppard was 20m away from Beau Waters' inspiring repeat defensive efforts against Port Adelaide in round two, with the half-back tackling twice and smothering before eventually winning the football and setting up an Andrew Embley goal.
Sheppard said the players had been rocked by Waters' elbow injury, with the vice-captain sidelined for three months, but his efforts would inspire everyone to lift their defensive work-rate.
"It was just awesome watching him do that, it lifts the whole team and it's just inspirational," Sheppard said.
"It's something I've got to improve and it's something everyone would like to work on and get better at.
"He's such a good leader out on the field and such a good bloke on and off the field, so you just feel sorry for him. He's put in such a good pre-season.
"We can't get too down though, because we've got other guys performing in the WAFL and it's pretty competitive for spots."
Sheppard has been omitted this week after a fortnight he describes as "indifferent", with premiership midfielder turned defender Sam Butler included to face the Sydney Swans at Patersons Stadium on Saturday night, alongside key defender Eric Mackenzie.
Sheppard, who has been given roles on small forwards and resting midfielders this season, said he, like the team, was focusing on the defensive aspects of his game.
"Playing in the backline, your first priority is playing on your opponent and beating them, and then the second part is trying to run off and create," he said. "That's my strength.
"I've just got to have the confidence to take the game on and play to my strengths while also helping the team out and nullifying my opponent in the backline.
"You feel a bit of pressure when you line up on a good forward, but I'll just keep backing my judgement and keep taking the game on."
