The Crusaders, on top of the Super Rugby table, face a season-defining match against their fiercest rivals in the Fiji capital, and Blackadder needs his No8 fit and at the top of his game, as he has been all year.
Watch: Patrick McKendry and Gregor Paul review the third test
So does All Blacks coach Steve Hansen. Read, the All Blacks' most important leader, a man who plays such an integral role in everything from the lineout to the team's defence and attack, may well be carrying mental and physical fatigue into the Suva match and beyond after three tough internationals. Assuming the Crusaders make the playoffs, Read will also have the added pressure of finals rugby to contend with before the Rugby Championship.
Highlanders coach Jamie Joseph is another who will have to walk a fine line. His team yesterday started their arduous trip to Port Elizabeth in South Africa, where they play the Kings, before travelling to Argentina where they play the Jaguares a week later. With key All Blacks in halfback Aaron Smith and fullback Ben Smith in his team, Joseph is also in charge of some precious cargo.
Asked about Read's welfare, Hansen said: "I'm concerned about all of them, I don't want any of them to get injured.
"But at the same time we can't wrap them up in cotton wool; we need them to play footy and they've got to play some big games and let's sit back and see how they cope with it. And the guys who do cope with it, that's a big advantage.
"It's going to be tough. It's tough for the athlete, first and foremost. It's bordering on ridiculous, really. A guy getting on a plane to go to South Africa the day after a test match, but that's the state of the nation, our competition at the moment.
"It's no one's fault. The Highlanders need their players to be there and unfortunately they have a draw which says they have to be in South Africa. But it is tough and that's why we are fighting for a global season.
"We don't want that [injuries]. But the hard rugby will be good because you get lots of answers about them at this time of year - but you want them to get through it without getting injured."