Dave Rennie faces a reshuffled selection puzzle ahead of Saturday's second Test in Cape Town, with Ethan Blackadder having delivered a statement performance in the All Blacks' 41-35 win over the Lions at Ellis Park on Tuesday.

Blackadder, who was left out of the starting squad for the first Test against the Springboks, was outstanding in Johannesburg — finishing with 16 carries, 70 metres gained, two tries, three offloads and two turnovers. Rennie acknowledged the loose forward was "all over the park" and praised his engine and post-tackle work.

"I think so," Blackadder said when asked whether he had played himself into Test contention. "Rens has been awesome like that, so the selections are in their hands."

The win itself was far from comfortable. The All Blacks trailed 17-35 before scoring four unanswered tries in the final 20 minutes to seal the result — a performance that will give Rennie as much cause for concern as optimism ahead of a Test match against the world champions.

Rennie's selection task is further complicated by the concussion suffered by lock Josh Lord, who is ruled out for Saturday. Tupou Vaa'i is expected to shift to the second row alongside Fabian Holland, with Patrick Tuipulotu also in consideration — a reshuffle that could open a starting or bench berth for Blackadder in the loose forwards.

Rennie names his matchday squad on Thursday.