McEwan is hard to beat in matchplay as he seldom makes errors which opponents can feed off.
But yesterday Borren (24) found the solution and, with the aid of a golden putting touch, took it to McEwan with four birdies in the first six holes to lead by four.
McEwan had beaten Brandon Hodgson (Otago) 3 and 1 in the morning semifinal while Borren accounted for Mathew Tautari (Southland) in a tight match which also finished on the 17th green.
Ryan Bellamy won the senior plate beating Sean Masters while Ryan Shuttleworth (Wanaka) defeated Jason Hughes to take senior B honours.
Sungwoo Han (Queenstown) won the senior B plate, Trevor Bolt took intermediate honours in a marathon playoff and schoolboy Will Young won the junior title.
In the main final, Borren made his presence felt on the first green sinking a 3m putt for a birdie four to take the lead.
He went two ahead sinking another 3m birdie putt on the second green and went three in front when McEwan hooked his tee shot and then had bunker problems at the third.
The pair halved the fourth in pars and McEwan had the inside running at the fifth with a 2m chance.
But Borren holed an 8m putt for a birdie three while McEwan's putt slid past the cup putting Borren four up.
At the sixth, McEwan came up short but chipped in for a birdie three. Borren was equal to the task and retained his lead of four making a 2m putt for his three.
McEwan fought back on the next two holes making a birdie from 12m on the par-3 seventh and a birdie three at the eighth to halve Borren's lead.
But his fightback came to an abrupt end on the 10th green when McEwan three-putted from the back apron for a bogey five.
Another three-putt by McEwan, this time on the 12th green, put Borren back in the driving seat at 4-up with six holes to play.
Borren pulled his approach into a bunker on the 13th and McEwan's par reduced the margin the three.
McEwan had another opportunity at the 14th but his 2m birdie putt slid past the cup on the low side.
The match finished on the 15th green when Borren holed a tricky sidehill 3m putt for a birdie two.
