From there, 16 of those 20 teams have gone on to reach the top eight by the end of the regular season, and 14 have finished in the top four.
Only four teams have plummeted, from top of the table in April to outside the eight by September.
It last happened in 2010 with the Melbourne Storm, though there were extenuating circumstances.
In round six of that season the Storm were hit with a number of penalties for their salary cap breaches, which saw them stripped of the 2007 and 2009 Premiership titles and unable to play for points for the rest of that year. They won 14 games, but ended the season in 16th place.
Today's opponents the Cowboys have twice missed the finals after winning their first four matches. In 2006 they got off to a flyer - taking their first six games - after reaching the grand final the year before. But they dropped eight of 10 matches mid-season, and also lost Johnathan Thurston late in the campaign.
In 1998 the North Queensland team won five of their first six matches before falling away, finishing 16th in the 20 team competition after only four more victories.
The only other instance of a club winning their first four games then missing the finals was Canberra in 2005, when Matthew Elliott's team slumped to 14th after a promising start to the season.
Nothing tangible has been achieved with the Warriors of 2018 but something different is in the air at Mt Smart.
"We want more," said prop Sam Lisone. "When you get that little taste, you want more. But we don't want to get carried away ... no one is doing that. Mooks [coach Stephen Kearney] will kick your arse, if he notices any of that."
Quick off mark
Clubs with 4-0 starts in NRL era
Melbourne 6, North Queensland 3, Newcastle 3, Brisbane 2, Canberra 2
Cronulla 1, Souths 1, Manly 1, Sydney Roosters 1
Fast starters that missed the top eight:
Cowboys 1998 (16th)
Canberra 2005 (14th)
Cowboys 2006 (9th)
Storm 2010* (16th)
*Due to points deduction