Former Kiwi international Krisnan Inu will replace Vatuvei for Sunday's match against St George Illawarra in Wollongong, and Vautvei will also miss the Warriors' final match of the regular season, against North Queensland in Auckland on September 3.
The 25-year-old winger played the full 80 minutes against Penrith last Saturday night, scoring his 10th try of the season - and the 88th of his career - to seal the side's 26-12 victory.
Head coach Ivan Cleary said the Vatuvei was expected to return for the first week of the playoffs on the weekend of September 9-11.
Inu's last NRL appearance was in the Warriors' 30-10 loss to North Queensland in Townsville on June 18. Since then he has been turning out for the Auckland Vulcans in the New South Wales Cup.
The swap is the sole change to the 18-man squad which travelled to Penrith. Lewis Brown, 18th man against the Panthers, is again on a five-man bench which also includes Lance Hohaia, Ben Matulino, Sam Rapira and Elijah Taylor.
The Warriors have won six of their last seven matches since their second bye, and now lie fourth, one of three teams on 30 points.
The Dragons have lost five games in a row, but Cleary reads nothing into their form.
"If anything it makes them even more dangerous. They're back in Wollongong and will be so desperate to get a win with the finals so close," he said.
"While we weren't at our best against the Panthers, we managed to get the result we were after. It won't be good enough against the Dragons."
Standoff James Maloney will play his 50th NRL match on Sunday and three players will extend their record of playing in every game this season, with captain Simon Mannering, Feleti Mateo and Ben Matulino all making their 23rd appearances this weekend.
Warriors: Kevin Locke, Bill Tupou, Joel Moon, Shaun Berrigan, Krisnan Inu, James Maloney, Shaun Johnson, Russell Packer, Aaron Heremaia, Jacob Lillyman, Feleti Mateo, Simon Mannering (captain), Micheal Luck. Interchange: Lance Hohaia, Sam Rapira, Ben Matulino, Elijah Taylor, Lewis Brown.
