Rory Best began his final Rugby World Cup campaign with a try as Ireland accelerated away from Scotland en route to an opening win.
Johnny Sexton and Rory Best led the way as Ireland's thumping win over Scotland affirmed their credentials as Rugby World Cup challengers.
Italy won a Rugby World Cup opener for the first time since 1991 after triumphing in their Group B clash in Osaka.
Johnny Sexton was taken off with injury against Scotland earlier this year and Gregor Townsend's men intend to get physical again.
Alun Wyn Jones has been lauded by Wales coach Warren Gatland as he prepares to rack up a landmark appearance against Georgia.
New Zealand started their Rugby World Cup campaign impressively but Steve Hansen said: "There's plenty of stuff we can work on."
A penalty count heavily in their favour was key to securing New Zealand victory over South Africa, according to Rassie Erasmus.
Six minutes of first-half brilliance against South Africa underlined why New Zealand are Rugby World Cup favourites once again.
Kieran Read was delighted New Zealand took the opportunities presented to them by errors from South Africa in the Rugby World Cup opener.
South Africa started vibrantly but were put to the sword by New Zealand in an incredible first-half spell that changed the game.