Genia and the Wallabies lost to Wales last November for the first time on his watch. He'd known nothing but victory against the Welsh since his test career began in 2009. He had 11 straight wins over them until the 9-6 defeat in Cardiff on a late Dan Biggar penalty.
"That's the only time I've lost (to them)," he said on Tuesday in Tokyo. "It hasn't changed my mindset heading into the game (this weekend) and I hope that's the case for the rest of the guys because we've had plenty of success against them."
Genia, who has two tries against the Welsh, said the key to victory against them was patience and perseverance. "They're happy to play without the ball for long periods of time. They back their defensive system, and back their workrate and fitness," he said. "In terms of breaking them down it's going to take patience, going to take holding on to the ball for long periods of time, and sort of being smart about how we attack as well."
The veteran scrumhalf said the Welsh were very disciplined in their approach to the game, with or without the ball. "Very, very good defensive side, so it's going to be very hard to break them down with ball in hand," he said. "They're also a very good kicking team, very good aerially, so they've got a lot of the fundamentals covered really well.
"(But) we're coming at them with a strategy that we think will expose any chinks we see." Genia's faith was such that he didn't bother, on his day off Monday, to watch live the Wales-Georgia match, in expectation of seeing enough video analysis this week.
His last match against Wales was his 99th cap, and he started the next week against England for his 100th. But since then, he has mainly backed up Nic White, and it's a role the Wallabies' starting scrumhalf through the 2011 and 2015 World Cups is content with.
"Whether I play five minutes, 10 minutes, 60 minutes, I'm more than happy," he said. "I don't mind. "I enjoy the working relationship with Nic White. We see the game in a very similar way, and that's good because it's not much of a change for guys around us."
His experience has also helped him watch the game from the stands and see what's working and what isn't. Last Saturday in Sapporo, he and the reserves noticed their forwards were gaining in ascendancy on Fiji while they were trailing on the scoreboard. Genia replaced White in the 51st minute with the Wallabies still five points behind. Genia said they needed to attack through the forwards more, and it worked. They scored two tries from mauls within the next 10 minutes and turned the game around. Australia won 39-21 from 21-12 down.
"A lot of people say, 'You're backed in a corner,' but we have complete trust in how we play the game, and have trust in the individuals who are out there as well to adapt on the run," Genia said. "The whole team adapted pretty well."
The same in the 2015 World Cup, when Australia played Wales in a pool decider at Twickenham. Genia was yellow-carded in the 56th minute for a cynical foul and didn't return. Australia was leading 15-6 at the time. Another yellow card dropped Australia to 13 players but they held on.
Apart from the disappointment of being sin-binned, Genia said his memories of that game were of awe. "Just an immense defensive effort," he said, recalling how Welsh winger George North was held up over the line, "then a couple of plays later they had a six-on-three and we snuffed it out and got a penalty."
"Just patience ... patience with the ball and without," he said, reiterating his theme. "We speak about that being a strength for them but it's going to be something that we have to have come Sunday as well."
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