England's newfound "winning mentality" can help seal a first series triumph down under, says Australia rugby icon George Smith.
The flanker, who excelled for Wasps in the Premiership this season, worked with England during the Six Nations.
Smith, 35, feels the Grand Slam victory plus the recent success of teams like Saracens will mean Eddie Jones' side face Australia with confidence.
"England are a form team generating a winning mentality," he said.
"They are Grand Slam champions and they've got players who were part of the (Saracens) Champions Cup-winning team, while there were three English teams in the semi-finals of the Champions Cup.
"You win some games, and your confidence grows, you win some more and your confidence grows, and you become a team that feels invincible."
Smith worked under England boss Jones at both the ACT Brumbies and Australia and was employed as a breakdown consultant for England as they topped the Six Nations in 2016.
But having won 111 caps for the Wallabies, Smith has no doubt over where his loyalties lie before the upcoming three-Test series.
"I'm supporting Australia, they're my home country," Smith told BBC Radio 5 live. "I'm looking forward to the series, and I'll be there watching in Australia, and cheering the Aussies on."
Smith will continue his illustrious playing career in Japan next season, but reflects with fondness on his year with Wasps.
"I've really enjoyed it this year," he added. "It has exceeded my expectations.
"I've been given nice opportunities throughout the year, with Wasps and with the English players, so it's been a very productive year. It's been fantastic."
Hear more from George Smith on the Matt Dawson Rugby Show on BBC 5 live at 21:30 BST on Wednesday night.
5 live will have exclusive live radio commentary on all three of England's Test matches in Australia. Coverage of the first Test in Brisbane starts at 10:30 BST on Saturday, 11 June.