Otago secured their place in one of the ITM Championship semi-finals with a 37-33 win over Auckland at the Forsyth Barr Stadium.
Auckland picked up two bonus points after running in four tries, with two for left winger George Moala, and also finishing within seven points.
The loss leaves Auckland six points behind top-placed Wellington in the ITM Premiership after ten matches.
Parker continued his fine points-scoring run for Otago with six penalties and two conversions, finishing the regular season with 156 points.
Buxton Popoali'i opened the scoring for the hosts in the eighth minute to cancel out Simon Hickey's early penalty, George Moala countering with his first try only three minutes later.
A free-flowing first-half saw plenty of open rugby as both sides against found the whitewash one of after the other, former All Blacks lock Tom Donnelly crashing over before Hadleigh Parkes responded for Auckland, Parker and Hickey trading penalties to leave Otago 21-18 ahead at half-time.
Auckland drew level with a Hickey penalty after the break before Grant struck for Otago's third and final try in the 46th minute.
Three successive penalties from Parker in ten minutes opened up a sizable 37-21 gap on the scoreboard for Auckland to chase, but despite Moala's second try in the 68th minute they were forced to leave it until the final few seconds when Lolagi Visinia went over to grab that bonus-point try and finish within seven points.
Tries: Popoali'i, Donnelly, Grant
Cons: Parker 2
Pens: Parker 6
Tries: Moala 2, Parkes, Visinia
Cons: Hickey 2
Pens: Hickey 3
Otago: 15 Tony Ensor, 14 Buxton Popoali'i, 13 Kieran Moffatt, 12 Jayden Spence, 11 Matt Faddes, 10 Hayden Parker, 9 Fumiaki Tanaka, 8 Paul Grant (c), 7 Lee Allan, 6 Gareth Evans, 5 Charlie O'Connell, 4 Tom Donnelly, 3 Scott Manson, 2 Liam Coltman, 1 Tama Tuirirangi.
Replacements: 16 Sam Anderson-Heather, 17 Aki Seiuli, 18 Ezra Taylor, 19 Willis Scott, 20 Josh Renton, 21 Peter Breen, 22 Teihorangi Walden.
Auckland: 15 Lolagi Visinia, 14 Tenina Sauileoge, 13 Malakai Fekitoa, 12 Hadleigh Parkes (c), 11 George Moala, 10 Simon Hickey, 9 Wayne Ngaluafe, 8 Peter Saili, 7 Kara Pryor, 6 Sean Polwart, 5 Jack Whetton, 4 Liaki Moli, 3 Ofa Tu'ungafasi, 2 Tom McCartney, 1 Pauliasi Manu.
Replacements: 16 Nathan Vella, 17Angus Taavao-Matau, 18 Luke Braid, 19 Sean Brookman, 20 Junior Poluleuligaga, 21 Piri Weepu, 22 Vince Aso.
Referee: Jonathon White