It was a conversation he couldn’t remember having with his wife that first prompted Penrith prop Nigel Plum to consider hanging up the boots.

But in the end it was a slight knock from a teammate on Friday that forced the NRL’s feared hitman to immediately retire after Saturday’s 24-10 win over the Warriors.

Having completed his 150th and final NRL match, Plum broke down with family before informing his teammates in the sheds that he was giving the game up due to repeated concussions.

It was the 32-year-old’s first game back after suffering a sickening head knock against Canberra in round 20 that he rated worse than another brutal blow he copped in Newcastle last season.

“I just had a few memory issues in the last couple of weeks,” Plum said after the game.

“When I forgot them at the time – I remember them now, which is a good thing – I just knew.

“I remember a conversation I had with my wife now, but I had forgotten earlier in the week.

“It was a conversation I had three weeks ago.”

The former Raiders and Sydney Rooster said that it was the first time he had suffered a headache through the night and complained of pressure every time he sneezed or coughed for the following week.

“I knew it was worse than what had happened before,” he said.

“All I could think about was my family. They come first in my life.

“During that week, I was really considering not playing again. But after I passed all the tests, it was clear I wanted to play again and wanted to finish the four games off.”

Plum had already intended to retire at the end of the season but a minor knock from a teammate during the captain’s run pushed him into pulling up stumps after the match.

“It wasn’t much at all. It was a little tap and it stung me for about five seconds,” he said.

“I was sweet from it, but it made me realise that what could happen in the game was a hell of a lot worse than what could happen in there.”

While it was repeated concussion that brought a premature end to his career, Plum said the game had made great strides in protecting its players from suffering severe head knocks.

“What the NRL is doing is fantastic,” he said.

“They have made some great steps forward in player welfare and having a few head knocks myself, I’m really happy about it.

“Obviously it’s only going to get better because they are doing some great things.”

Plum made his NRL debut with the Roosters in 2005 before spending three years in the nation’s capital between 2007-09.