Grey, a retired Christchurch salesman, won the Masters Games over 60 gold medal at the Dunedin Stadium, when he beat Morry Nielsen-Vold (Dunedin) 11-10 in a nail-biting finish.
It was the first major title Grey had won in 13 years of indoor bowls.
He had won the South Island Chartered Clubs fours two years ago, but this was the big one.
Nielsen-Vold, a retired special needs teacher, had previously won a bronze medal at the Masters Games and was looking for the gold.
He started aggressively and led 4-0 after two of the 12 ends.
Grey lost some of the composure that characterised his game in the early rounds.
His game improved as he let the pressure of the final go and relaxed into his game.
"I just tried to draw close," he said. "That has always been my game."
He accurate draw bowls brought him several touchers during the middle phase of the game, from the third to the sixth end, and he led 7-4 after the sixth end.
He added two more on the eighth end, to lead 9-5 with just four ends left.
Nielsen-Vold varied his play and nudged the jack around, upsetting Grey's rhythm.
The ninth end was critical for Nielsen-Vold if he was to stay in the game.
He trailed the jack back for two and added the bonus shot to reduce the gap to one.
On the 10th end, Nielsen-Vold pushed the jack back to his own bowl and took two more shots.
Grey's attempted rescue shot went off the mat and Nielsen-Vold led 10-9.
Grey pulled a shot back on the penultimate end to level the score at 10-all before the final end.
Both bowlers were feeling the pressure and the first four bowls were loose and off the mark.
Grey came closer to take the shot with his third bowl.
But it was still 6cm short of the jack.
He added a second shot with his last bowl.
Nielsen-Vold could only nudge in for second shot with his last bowl and the game was over.
Dunedin bowlers Derek Keane and Don Crawford both won bronze medals.
The over-40 final was one-sided, with the experienced Craig Cowan beating Andrew Thompson (Eastern Districts) 14-7.
