Bagrie-Howley (21), an aviation restoration technician from Gore, came from behind to win the Scottish Open singles qualifying event at Westpac Bowls Stadium.
If he wins the national final in Dunedin in September he will compete in the Scottish Open singles in Perth in November.
He beat Doug Thomas (North East Valley) 2-9, 16-5, 2-0 in a closely-fought final.
Bagrie-Howley, who started playing bowls at the age of 10, was a member of the New Zealand development team for this year's Trans Tasman series in Christchurch.
He won a silver medal in the mixed pairs at the world junior championships last year and has won six Southland titles.
Thomas, who competed in the world indoor singles in 2007, controlled the jack and played long ends to dominate the first set.
Bagrie-Howley had the choice of taking the mat in the second set and played short ends.
"I took the mat up to the very front limit,'' he said.
"I couldn't get my length on the long ends.
"But on the short ends I got my weight control back again and was able to adjust better on the longer ends when Doug had the mat in the third set.''
The crucial time in the second set for Bagrie-Howley came on the third end when he led 3-2.
Thomas held one shot on the head but Bagrie-Howley played a weighted shot with his last bowl that pushed the shot bowl off the head and ran his own bowl through for three shots and a 6-2 lead.
On the next end, Thomas was two down on the head and had missed with two drives. Disaster came with his fourth bowl when he drove out his own two shots and gifted Bagrie-Howley four shots and an unbeatable 10-2 lead.
In the deciding third set, Bagrie-Howley drew more accurately than Thomas and won 2-0.
In the semifinals, Thomas beat Andrew McCallum (Anderson's Bay) 14-1, 9-8 and Bagrie-Howley beat Russell Dawe (Kaikorai) 6-7, 8-7, 2-0.
Black Jack Andrew Kelly (Redcliffs, Christchurch) won the Shanghai singles final with 31 points ahead of Aidan Lusby (Andersons Bay) on 26 and Andy McLean (North East Valley) on 19.
The former Oamaru bowler won two gold medals for the Black Jacks at last season's Asia-Pacific Championships and represented New Zealand in the Trans Tasman and Six Nations championships.
Kelly (28) started with a five on the first end and ended the game on the 12th end with another five when leading by just one point from Lusby.
Lusby was one point ahead of Kelly after seven ends with 16 points. However, a six on the eighth end gave Kelly a five-point cushion that he never surrendered.
In the semifinals, Kelly and Lusby shared top spot with 30 points with Murray Wilson (Fairfield) third on 28 points.
McLean won the other semifinal with 31 points from Ross Stevens (St Clair) 28.
Four players called the joker successfully during the Shanghai competition to gain 12 points on an end. They were Murray Wilson, Brent McEwan, Paul King and Glen Murtagh.
