Otago, playing with real vigour and aggression, blew Wellington off the park in the second half at Carisbrook on Saturday night.
Down 14-3 at half-time, the home side scored five tries in the second half and put competition leader Wellington firmly in its place.
Otago finally played the game it had wanted to all year.
There was plenty of passion and commitment, and it never took a backward step in the second stanza.
The hesitancy and fumbling of the past weeks was gone, tackles were made and passes found the man.
Although there was nothing riding on the match, with Wellington already qualified top and Otago out of the running for quarterfinals, the home side showed its season was not a total letdown.
The star of the show was All Black Adam Thomson whose return energised the home side.
Thomson, who re-signed for Otago for two more years earlier in the week, was all over the park and picked up two tries.
He pilfered plenty of ball at the breakdown and was a constant threat with ball in hand.
His skills and pace as an openside flanker were a pleasure to see for Otago supporters, and would have pleased watching All Black coaches Wayne Smith and Steve Hansen, who were in the stand.
The 26-year-old now appears the obvious back-up to All Black captain and openside flanker Richie McCaw.
His first try came from a quick tap when he burst through a gap 20m out, pushing off replacement lock Jeremy Thrush.
The second was the icing on the cake for Otago, with 4min to go, picking up a bad pass in the Wellington backline and skipping away to score.
That try was converted by skipper Craig Newby, who bid goodbye to Carisbrook in fine style.
Newby has always been a committed player and that was reinforced on Saturday night.
He put in a 50m sprint midway through the first half to deny Wellington midfield back Michael Hobbs a try in the corner.
He may have cost Otago a penalty by knocking the ball dead, but the act was an inspiration for his side.
Newby had his best match of the season.
He made plenty of tackles and was effective at the breakdown.
Newby's experience will be missed but new boys Dan Snee and Andrew Parata in the middle of the Otago backline showed there are some wise heads still around, tackling well and showing composure under pressure.
Winger Karne Hesketh scored Otago's first two tries, giving him seven for the season and surely sealing a Super 14 berth.
His first came from a good draw and pass by hooker Peter Mirrielees, while halfback Sean Romans burst through some slow Wellington forwards to set up Hesketh's second try.
Wellington butchered some golden opportunities in the first 40min, although it did pick up two tries.
The Lions looked comfortable at the break, but threw too many speculative passes in the second half and turned over too much ball.
That led to two Otago tries, while Otago also grabbed another couple of intercepts.
Daniel Kirkpatrick missed an easy penalty midway through the second half which in the end was costly.
The Wellington line-out worked well and departing lock Ross Filipo had a top game, but it missed talents such as Cory Jane and Hosea Gear.
Otago 36 (Karne Hesketh 2, Adam Thomson 2, Alipate Fatafehi tries, Chris Noakes penalty goal, Noakes 3 conversion, Newby conversion), Wellington 21 (Tu Umaga-Marshall, Scott Fugistaller, Ma'a Nonu tries, Daniel Kirkpatrick 2 conversions, Fa'atonu Fili conversion).
Half-time: 14-3 Wellington.
Crowd: About 3500.
