Sportal.co.nz 27.Sep.2012Getty Images
Southland gained their third consecutive win and now have 15 points and are among a group of teams vying to make the semi-finals.
And Cowan, in his 102nd and last game for Southland, kicked the ball into touch to end the match before he was swamped by Stags supporters.
"We pride ourselves at home, we're building and I'm sure we'll finish the competition well," Cowan told SKYSport.
"It's very emotional. I've been here 12 years and it's a province I'm very proud and very fond of. That's it for me. It's been a great chapter of my life and I'm sure the others will create their own legacy in time."
Cowan will leave later this week to take up a contact with English club Gloucester while the Stags' next assignment is against Canterbury in Christchurch on Sunday.
The difference in the end on Wednesday night was discipline and goal-kicking. Scott Eade kicked three penalty goals from five attempts and the Stags did not concede a kickable penalty until late in the game.
Stags' captain Jamie Mackintosh was pleased with the first half but lamented the fall-off in the second.
"We're rapt to get away with a win but it would have been nice to put two good halves together," he said.
Northland acting captain Rene Ranger was pleased with the Taniwha second half comeback and the losing bonus point took them to 16 points.
"But I was disappointed with our execution and handling errors. That cost us, and we also have to protect our ruck ball better."
Northland's next game is against Bay of Plenty in Mount Maunganui on Sunday.