Southland, which won its first title last year, came through on a tough day, thanks to a convincing 4-1 win over Auckland in the afternoon, which will see it take on Bay of Plenty in the semifinals.
The other semifinal will have Tasman lining up against Manawatu-Wanganui.
Otago could not get over the line and into the semifinals yesterday, as results did not go its way and it lost its final game.
It eventually finished 10th.
Tasman came charging through the ranks yesterday, toppling Bay of Plenty in the morning and having no trouble disposing of North Harbour in the afternoon, eventually finishing top of its division.
Bay of Plenty struggled at times yesterday, losing 3-2 to Tasman in the morning and then only managing to halve its game with Canterbury in the afternoon.
But its earlier performance in the week was enough to get it into the final four.
Manawatu-Wanganui had started poorly on the first day but has slowly been getting its game together and had two good wins yesterday, beating Waikato 3-2 and then getting the better of Taranaki, 4-1 in the afternoon.
Southland had just squeezed past Wellington 3-2 in the morning but was more emphatic in the afternoon, getting the better of a young Auckland side.
A strong southwest wind made conditions tricky yesterday and the ground staff worked hard in the morning to get water off the greens so play could start on time.
Otago lost 3-2 in a nail-biter to Northland in the afternoon, after having a bye in the morning. It needed Bay of Plenty to beat Tasman in the morning to help it, but that did not happen.
Otago's afternoon match was full of drama and one which did not end until the final green of the last pair.
Brent McEwan had played a miracle shot to get back on to the green but his putt to square the match just slid by.
McEwan had earlier played his second shot left-handed, as his ball was lying under a tree and he could not find the green if he played an orthodox right-hand shot.
Instead he turned his club over, took a left-hander's stance, and proceeded to hit the ball 140m on to the green.
It was an extraordinary shot but ultimately came with no reward.
Earlier, Otago No 5 Tony Giles was forced to concede the third hole after he mistakenly hit the wrong ball.
He had checked his ball but found after he hit on to the green he had hit the wrong one.
A spectator later discovered Giles' ball about 15m from where Giles mistakenly played.
Both balls were marked exactly the same, with the same numbers and it was a most unfortunate mistake. He later lost on the 18th green.
McEwan was disappointed with the loss, especially after the support all the team had received this week.
''The support we have had throughout the week has been great and we wanted to held repay them,'' McEwan said.
Otago No 2 Michael Smith, who won yesterday, said it was a shame they were not playing in the semifinals.
''It would have been great to play in front of our home crowd. But things just did not go our way, little things which did not help us, right throughout the week,'' he said.
''The loss to Tasman really cost us. They won 5-0 but it could have so easily been 5-0 to us.''
Otago finished with a record of three wins and three losses, tiring in the home straight after winning its first three matches.
The semifinals start at 7.30am today and the final is due to start at 12.30pm.
