A break from Brendon Gotuno presented the Vipers with the first opportunity to score.
Fast hands put Rex Tandowa over to score out on the wing in the 14th minute.
Repeated sets to the Vipers had the defending champions under the pump but one mistake from the Vipers turned the tide.
A short ball from Noel Joel sent a charging Casey Dickson in for the Tigers’ first points.
Former Gurias star now Tigers halfback, Jason Missian, added the extras to put his side in front after 26 minutes.
The Vipers responded twice with tries to Manu Kame and Gotuno to take back the lead.
But this was all undone with a Tandowa error from the restart.
After being awarded a penalty with less than a minute before the break, the Tigers opted to kick for goal and converted to trail 16-8 at half-time.
Five minutes into the second half, the deficit was further reduced after Charles Martin proved too strong to stop near the line.
Missian then hooked it from the sideline to bring the score to 16-14.
Points were hard to come by and the Vipers also made the decision to kick for goal through Benton Leme, who sailed it through the posts to give the Vipers some breathing space.
Poor ball control from both sides blew any more opportunities for points with the Vipers clinging on to register their first win of the season after three rounds.
"I'm really happy with the boys, but we still have a lot to polish up on," said Vipers coach, Joe Sipa.
For the Tigers, this is their second loss this season.
"We were our own worst enemy today," said Tigers coach, Stanley Tepend.