The Chiefs survived an early onslaught to beat the Waratahs 30-13 at Waikato Stadium in Hamilton on Saturday but failed to secure a bonus point.
The Waratahs chances of reaching the play offs are rapidly slipping away from them as they have played six Super Rugby matches and only one two.
In contrast the Chiefs moved up to fourth place on the points table on 22 points with a record of played five and won four.
Current leaders the Highlanders also have 22 points but have one more victory so they top the standings.
The Waratahs enjoyed 72% territory and 66 % posession in the first half but the Chiefs led 13-10 at the break.
The second half was an entirely different affair as the Chiefs pulled the stats back into their favour and outscored the Waratahs by 17 points to 3.
The Chiefs played with great intensity in the second half but could not get over the tryline for the bonus point try.
Prop Sona Taumalolo scored his fourth try in five matches and flyhalf Aaron Cruden kicked six goals from six attempts in the match.
Taumalolo, the Chiefs' leading try scorer this season, touched down shortly after halftime to lift his team to a safer 10-point advantage after it had taken a 13-10 lead.
Cruden kicked three conversions and three penalties for 15 points to continue his outstanding goalkicking form and to clinch the Chiefs' fourth win of the season, keeping pace with the Highlanders at the top of the New Zealand conference.
The Waratahs made all of the play in the first half, dominating possession and territory, and were shocked to find themselves behind when the teams headed to the locker rooms for the halftime break.
The Chiefs had demonstrated more enterprise in the first half, attacking dangerously from deep defence, and when they gained a set-piece platform in the second half and played with more ball from stronger field position, they ran over the Waratahs.
The Waratahs continued a stuttering start to the season: after two losses, they rebounded with a win last week over South Africa's Sharks.
But Saturday's loss set them back and left them firmly in the bottom half of the championship table.
A solid scrum, improved lineout work and outstanding play from key backs set up the Chiefs' fourth win from five games, though they narrowly missed the bonus point that would have taken them clearly to the top of the overall table.
Cruden, winger Tim Nanai-Williams, center Sonny Bill Williams and fullback Robbie Robinson were key contributors to the Chiefs' effort on Saturday which eventually overwhelmed the more staid Waratahs.
The Waratahs scored the first try of the match through winger Tom Kingston after only five minutes and led 7-0 after the conversion from scrumhalf Brendan McKibbin.
But the Chiefs struck back against the run of play with a try to Robinson and Cruden's conversion which brought them level.
McKibbin kicked a 24th-minute penalty that gave the Waratahs a 10-7 lead but that was the last advantage they enjoyed in the match.
Cruden drew the Chiefs level again in the 30th minute and kicked a 34th-minute goal which allowed them to take a three-point lead to halftime.
Taumalolo scored a try three minutes into the second half. A speculative chip kick from Williams bounced into the arms of center Richard Kahui and he fed Taumalolo, who was hovering unmarked, on the right wing.
McKibbin kicked his last goal in the 48th minute, cutting the lead to 20-13, but that was the Waratahs ' last scoring play.
Cruden kicked his fifth penalty, then added the conversion of a 67th-minute try to flanker Liam Messam to give the Chiefs their final 17-point margin.
Final Score Chiefs 30 (13) Waratahs 13 (10)
Tries - R Robinson, S Taumalolo, L Messam
Pen - A Cruden 3
Con - A Cruden 3
Tries - T Kingston
Pen - B McKibbin 2
Con -B McKibbin
Referee: Mike Fraser
Assistant Ref 1:Jonathon White (New Zealand)
Assistant Ref 2:Glen Jackson (New Zealand)
TMO :Shane McDermott (New Zealand)
1. Arizona Taumalolo , 2. Hika Elliot , 3. Ben Tameifuna , 4. Craig Clarke (c) , 5. Brodie Retallick , 6. Liam Messam , 7. Tanerau Latimer , 8. Kane Thompson , 9. Tawera Kerr-Barlow , 10. Aaron Cruden , 11. Tim Nanai-Williams , 12. Sonny Bill Williams , 13. Richard Kahui , 14. Asaeli Tikoirotuma , 15. Robbie Robinson
Replacements : 16. Mahonri Schwalger , 17. Josh Hohneck , 18. Michael Fitzgerald , 19. Sam Cane , 20. Augustine Pulu , 21. Andrew Horrell , 22. Lelia Masaga
15. Bernard Foley , 14. Tom Kingston , 13. Rob Horne , 12. Tom Carter , 11. Adam Ashley-Cooper , 10. Berrick Barnes , vice captain , 9. Brendan McKibbin , 8. Wycliff Palu , 7. Chris Alcock , 6. Dave Dennis , 5. Kane Douglas , 4. Dean Mumm , 3. Sekope Kepu , 2. Tatafu Polota-Nau , 1. Benn Robinson , captain
Replacements , 16. John Ulugia , 17. Paddy Ryan , 18. Sitaleki Timani , 19. Lopeti Timani , 20. Jono Jenkins , 21. Sarel Pretorius , 22. Daniel Halangahu