Speaking to the Herald on Sunday, Eales did not want to divulge details of private conversations with Horwill but says he has a mandate to lead Australia's challenge for a third World Cup crown.
"James has been successful and is respected by everyone. He came into the Reds leadership quite young [at 23] which would have been daunting but he's got increasingly better as a leader. While results don't tell the whole story, they're an indication he is well accepted."
Last weekend's result had shades of the final Tri Nations test before the 1999 World Cup. Australia won that match 28-7 over the All Blacks and triumphed at Twickenham in November. Eales says last weekend was a significant leap after the Wallabies' string of losses to the All Blacks in recent years under coach Robbie Deans.
"A result like that gives you a sense of belief you can win when the pressure's really on. You can't attribute that win to one thing. They've been working hard as a team for a long period. Saturday was a breakthrough on the back of some good performances.
"While All Black teams have had the odd defeat in the last couple of years, they've never been beaten in a game that meant a lot with both sides at full strength. That was the difference; there was something on the line."
Conversely Eales believes another factor helped the Horwill transition: "You have to admire the way [former skipper] Rocky Elsom reacted so maturely. That has been an important response. It would have been hard for Rocky to take but he's still an important part of the team."
Eales' observation underlines a subtle fact. In the modern day of instant communication, Elsom and Horwill kept the decision quiet for three days without a tweet or Facebook posting in sight - there is clearly honour and respect there.
Deans had a further reason for making the switch. Scott Higginbotham's form
has been outstanding with the Reds this season on the blindside. It would have been embarrassing if Deans had to drop Elsom during the World Cup.
Horwill's elevation comes after leading the Reds to their first Super Rugby title under coach Ewen McKenzie. They beat the Blues and Crusaders in consecutive weeks to triumph in Brisbane.
McKenzie says Deans has made the right move despite it being so close to the World Cup. All Black David Kirk was the least experienced World Cup-winning captain, with just four tests in charge heading into the 1987 campaign.
"I don't see it as a risk," McKenzie says. "I'm a big fan of change if you're not getting what you want: it can be necessary, imperative but sometimes complicated because Rocky played a significant role beating South Africa the week before. It probably caught a lot of us on the hop but such calls are often a catalyst to creating momentum and enthusiasm.
"They've picked a quality guy who'll do everything possible to win the Cup. He's got a physical presence and his work ethic is good around the team. He's always at things, not just corporate functions, but under-12 this and under-15 that; a school thing here, a sports day there. He's doing up to 10 promos a week outside of the things we ask him to do.
"For me, that's total leadership and being an ambassador for the game; it's easy to find reasons not to do things. He's a good listener - an underrated quality. It's easy to talk but listening shows how well you absorb messages.
"He never pretends he's got it all covered and is willing to take advice. As a result, the Reds were the best team of open-minded players I have been involved with."
