Halfback Ellis strained a calf in the final drill of the warm-up before his team's 35-10 defeat to the Hurricanes at AMI Stadium, while wing Nadolo strained a hamstring during the match.
The injuries could represent the end of two contrasting but equally important playing careers at the franchise. Ellis, who has played more than 150 matches for the red and blacks and is a key cog in their backline, is retiring after this season, while Nadolo is moving to France after a high-impact three seasons at the franchise.
The travel schedule to Johannesburg will also play a part, although the Lions have a difficult schedule themselves getting home from Buenos Aires.
Blackadder's team are unable to leave for the Republic until Tuesday due to a lack of flights. Even should they win at Ellis Park, the short turnaround after their long-haul flight, plus another long flight back to New Zealand to play the Hurricanes in the semifinal, will leave them severely disadvantaged.
Blackadder, who viewed the Jaguares v Lions game and thought his side would be travelling to Wellington for a rematch against the Hurricanes for their quarter-final until the Argentine side turned it on to win 34-22, said the time in Christchurch over the next few days would be spent recovering physically from their loss to the Hurricanes.
Lock Sam Whitelock, named in the starting line-up to play Chris Boyd's team despite falling ill with a virus during the week, was a late withdrawal, but should be well enough to travel. Several players in his squad had fallen ill during the week, Blackadder said.
"If anything it will give us a chance to freshen up and allow us to take a fit team away," he told the Herald on the way to a logistical meeting at his franchise's headquarters.
"This is the time of the season when you need to be together as a group, and our time in South Africa will help us do that."
Perhaps unlucky to concede a try on the stroke of halftime at AMI Stadium, which cost them the lead, the Crusaders failed to fire an attacking shot in the second half. The Hurricanes were also disadvantaged when losing Ngani Laumape before kick-off, but the re-jigged midfield of Willis Halaholo and Jason Woodward cut the Crusaders to pieces at times.
"I was disappointed with our performance, but I take nothing away from the Hurricanes, they played well and put us under a lot of pressure. We knew they would bring line-speed on defence and we failed to cope with it, so there is a lesson there."
The defeat was the Crusaders' fourth this year -- all have come against New Zealand opponents, with the Chiefs (twice), Highlanders and now Hurricanes proving too good. Blackadder has yet to announce his intentions for next year -- recent reports in the United Kingdom suggest he and assistant Tabai Matson could be heading to Bath -- but his time at the franchise will soon come to an end.
"Everything now is a one-off game," he said.
