Stuart Barnes says the British and Irish Lions' hopes of forcing a series decider rests on the game management of Johnny Sexton and Owen Farrell.
Warren Gatland has opted for start the two playmakers for Saturday's must-win second Test in Wellington, with Ben Te'o dropping to the bench despite an impressive showing in last week's 30-15 defeat at Eden Park.
Sexton and Farrell have played just 74 minutes together, including the final 23 during the first Test, and with wind and rain forecast for Wellington on Saturday, former Lions fly-half Barnes says they must pressurise the New Zealand back three.
"That's the absolute key, decision-making from Sexton and Farrell," he said.
"I think what you're going to see is Sexton to the left, Farrell to the right - a two-tier game with different kicking to make it difficult for Israel Dagg and the All Blacks back three.
"If the Lions are to win this game, they have to win not just a lot of possession but an awful lot of territory. And if they get territory they have to turn that into points.
"Behind the scrum they keep saying it's just a matter of finishing. I don't think the skill levels are good enough in the backs to score too many tries. Can the forwards weigh in with some scores?
"Twelve years ago in Wellington this was the day Dan Carter ascended to the throne of the king of fly-halves. Will Beauden Barrett be the man on Saturday?
"The Lions will be hoping that their press defence, the wind and rain will turn it into a very different story 12 years on."
Stephen Ferris believes the Lions pack will stand up and be counted in Westpac Stadium, giving Sexton and Farrell the time and space to make the right decisions.
"They'll have a couple of set plays up their sleeve," said the former Ireland and Lions flanker. "They put the Kiwi lineout under pressure last week with five steals; they've got to keep putting the squeeze on.
"When they get to within five metres of the All Blacks line, they've got to try and regain possession, get into some multi-phase and get the big boys going forward, breaking the gain line. Hopefully then we'll see a few more tries."