Ireland stunned the All Blacks to make history with their series-clinching third Test victory in Wellington on Saturday.
A few hours later England recorded a rare away series victory against the Wallabies, just the second in Australia by the Red Rose side in more than a century of rivalry.
AFP Sport looks at five talking points from the bruising tours to New Zealand and Australia:
- Keep your head -
Concussions blighted both series with World Rugby forced to clarify their head injury rules and return-to-play protocols.
England trio Tom Curry, Sam Underhill and Maro Itoje, All Blacks lock Sam Whitelock, Ireland centre Garry Ringrose and Australia's Allan Alaalatoa all were forced to miss matches after taking knocks to the head.
Confusion about the results of pitchside Head Injury Assessments (HIAs) prompted a statement from World Rugby after Ireland captain Johnny Sexton was selected for the second Test in Dunedin despite leaving the game after failing an HIA during the opener in Auckland.
The governing body noted that failing a sideline HIA did not confirm concussion and in Sexton's case he had later passed second and third HIAs, which meant he was not subject to "return to play protocols" requiring a player to rest for 12 days.
Progressive Rugby, a lobby group whose members include medical professionals, objected, saying the game's priority "must be to err on the side of caution".
- Card sharps -
World Rugby's push for the use of red and yellow cards to promote player safety became more confounding as both series unfolded, with coaches complaining as sides were frequently reduced in numbers.
"Accidental head contact, and this (excessive) use of TMO (television match official), we've got to cut out," complained England coach Eddie Jones.
He said he did not ever want to see again a match like the second Test in Dunedin where New Zealand received two yellow cards and a red and were at one stage down to 13 players.
"Imagine in the World Cup, you're playing a quarter-final, you get a red card, two yellows and you're down to 12 men, it's just ridiculous."
Jones and New Zealand counterpart Ian Foster both called for common sense and cards to be kept in the referee's pocket where there is an accidental clash of heads.
Jones and Wallabies coach Dave Rennie were also unhappy at yellow cards being given for legitimate interception attempts deemed a deliberate knock-on.
- Green giants -
Becoming the first team in the professional era to win a rugby series on New Zealand soil ranks as one of the great Irish sporting achievements.
Instead of buckling after losing the first Test by 23 points at Eden Park, they responded with the perfect blend of belligerence and clever rugby to dominate the next two, at times making the All Blacks appear second rate.
Playing a sophisticated, up-tempo style that has long been the domain of New Zealand, Andy Farrell's brilliant team will climb to the top of the world rankings on Monday and have marked themselves as a major contender at next year's World Cup.
- Foster in peril -
The New Zealand head coach has a tenuous hold on his post after their reputation took another blow at the hands of the well-drilled Irish, with New Zealand Rugby launching a review into the series defeat.
Sixteen wins from 24 Tests under Foster, and one from his last five, represents a dismal return by All Blacks standards and a vast drop-off from the dominant records forged under predecessors Graham Henry and Steve Hansen.
"The performance across the series for the All Blacks was not acceptable," said New Zealand Rugby CEO Mark Robinson as he announced the "immediate" review.
Critics were quick to point out that New Zealand's only win of the Ireland series, in the first Test, occurred after Foster and three of his assistants had minimal involvement after testing positive for Covid.
- England emerge -
England headed to Australia under pressure after a poor Six Nations campaign and a dire defeat to the Barbarians, but leave with a young team taking huge experience from a come-from-behind win in a pressure-cooker series.
While the trusty boot and tactical nous of Owen Farrell again proved pivotal, along with the experience of Courtney Lawes and Billy Vunipola, exciting young fly-half Marcus Smith and fullback Freddie Steward grew in stature.
Coach Eddie Jones blooded several others, notably teenage back Henry Arundell, wing Tommy Freeman and centre Guy Porter.
"They understand (now) how hard they have to fight to win a Test match away from home," said Jones. "We are in a good position (ahead of next year's World Cup)."