BRISBANE, AUSTRALIA - MAY 06: Shaun Johnson of the Warriors passes the ball during the round 10 NRL match between the New Zealand Warriors and Penrith Panthers at Suncorp Stadium on May 06, 2023 in Brisbane, Australia. (Photo by Bradley Kanaris/Getty Images)

New Zealand Warriors head coach Andrew Webster has revealed star half Shaun Johnson came 'super close' to not playing in the club's semi-final against the Newcastle Knights in Auckland on Saturday.

The Warriors, who played their qualifying final a week prior without Johnson who was battling a calf injury, thumped the Knights 40 points to 10 to book a preliminary final with the Brisbane Broncos next Saturday evening in Brisbane.

Johnson only trained at the captain's run prior to the game, but passed fit and played a superb game in pulling apart the Knights before being pulled from the field in the final minutes of the game by Webster.

The coach admitted Johnson came close to not playing, and that the Warriors had no clarity on whether he would take to the field until the captain's run.

"He came super close to not playing. But, we literally didn't know until yesterday," Webster said during his post-match press conference.

"What we said was truthful all week. We were confident that yesterday [the captain's run] was going to go well, but we weren't sure.

"We made sure we got him to the start line today, and he made sure he got himself to the start line. Not only did he get himself there, I thought he had a big impact and gave everyone confident. Everyone fell into shape and I thought our attack early was a big result of what he was doing."

Despite not training all week, Johnson was among the best for the Warriors, running on two try assists and running for 94 metres.

Captain Tohu Harris said Johnson missing training was never going to be an issue.

"I'm very happy for him that he got over the line. He would have been very disappointed if he didn't make the game tonight. He is someone who will do everything possible to get his body right, so that wasn't a concern" Harris said.

"In terms of missing training sessions and stuff like that, it was never an issue for the team. His calmness, and he knows our plan better than anyone in the team. Missing training sessions was never going to be an issue. We knew he was going to slot in there and do a job."

Webster admitted there was a chance Johnson wouldn't be able to train again during the week leading up to the Brisbane game, which will decide a spot in the grand final.

"I've got no idea. The reason I don't know is that he could pull up really good. I could get an extra training session out of him instead of just captain's run. If not, we will stick to the formula, but we will see how he pulls up," Webster said.