English loose forward James Haskell and former All Black utility back Tamati Ellison are both playing in the Japanese league for the Ricoh Black Rams.
The Japanese club season is nearing its conclusion and the play-offs start next week.
Highlanders coach Jamie Joseph said whether the Rams make the play-offs would be decided this weekend in its game against Toyota.
If the Rams lose, they will be out of the play-offs and both Haskell and Ellison will be free to come to New Zealand and link with the Highlanders next week.
But if they win the pair will spend the next few weeks in Japan in the finals series, and will not be heading south until the week the Super 15 kicks off.
Joseph said the franchise was always aware about when the pair would arrive and there was no concern about their late arrival.
"We knew that when we contracted them that was the case, and when the season was finishing over there and they could be in the final," he said.
"But they are quality players and playing rugby in a finals competition can only help them. It is a long season and they will be here for almost all of the season."
The Black Rams also have All Black Ma'a Nonu in their side and he will miss the first two rounds of the Super 15 competition for his new side, the Blues.
Joseph will also have to do without All Black winger Hosea Gear on Friday when the side plays its first pre-season game against the Crusaders in Greymouth.
Gear had wanted to play in the Wellington Sevens tournament this weekend and Joseph said he fully supported the former Hurricane lining up for New Zealand.
"I think playing sevens can only be good for us. It will sharpen him up and get him really involved, plus it allows a few guys who didn't get much of a go last year to show their wares on Friday."
Gear had played sevens for New Zealand at the Commonwealth Games in 2010 and that had kicked his season on as he starred for the All Blacks in the end of year tour.
All Black first five-eighth Colin Slade has come through a hernia operation successfully and Joseph said it was touch and go whether he would play the first match. Slade had the hernia operation last week and was back in light training.
Other injured players were improving, but Joseph said he did not want to rush players back on to the paddock too quickly.
New Crusaders recruit Tom Donnelly's pursuit of an All Blacks recall will have a good start when he takes on his former Highlanders team-mates in the opening Super Rugby pre-season match in Greymouth on Friday night.
Todd Blackadder has named lock Donnelly, a veteran of eight seasons with the Highlanders, to start with Ross Kennedy - a partner in the Otago NPC team for two of those seasons - in the second row.
Rejected by the Highlanders after he did not seem to fit with Joseph's vision, 30-year-old Donnelly is looking forward to Friday.
"I'm sick of pre-season training, really, and really looking forward to playing," he said.
"It just happens to be against the Highlanders, but pre-season games don't mean much. The round two clash down at the new stadium will be the big one."
It is a watershed year for Donnelly, who has played 15 All Black tests and been on the losing side only once, against the Wallabies in Hong Kong. He had a great Tri Nations for the All Blacks in 2010, so where did it go wrong last year?
"I don't know. I wish I knew the answer," he said. "I had a few niggling injuries right from the start of the season and they sort of played me through them and I didn't play very well for the Highlanders, and I suppose it led on one thing to the next and non-performance led to non-selection."
He had to prove himself to the Crusaders players and coaches, but had had his best pre-season for a while "and it's been really healthy for me".
His arrival offsets some of the loss of second-row experience from the departures of Brad Thorn and Chris Jack.
"They [the coaches] just said they don't treat me as a rookie up here," he said. "They just expect me to sort of do what I do best, and that's run the lineout and lead from the front, and help some younger guys in that team."
- Additional reporting Nick Tolerton, of the Christchurch Star
