Asano launched the 3yr-old down the outer for what proved to be a perfectly timed late burst to put a nose margin on runner-up Live Drama to win the 1355m listed feature.
The victory came after Asano had won eight consecutive races across two meetings.
The Japanese-born apprentice won the last five of six races at New Plymouth on Thursday, then rode the first three winners at the Gore meeting.
Lightning Jack’s win, which followed Asano’s victory on Rocanto in race 6, rounded out another haul of five winners for the jockey on Saturday.
Asano’s recent feats continued an epic run of form that has him leading the national jockey’s premiership.
His win on Lightning Jack still impressed the jockey, despite him making winning races such a regular occurrence.
"What a day, what a day," Asano said. "The trainer told me he was working well and the horse, he just went so hard.
"We needed a bit of cover, although it is hard to come from the back today.
"Around the corner I thought we still had some energy and he just flew home. Only good horses can do that."
Kelvin Tyler was convinced he had a good horse on his hands before the Gore Guineas.
The trainer thought enough of the 3yr-old to start him in the group 1 Two Thousand Guineas before Lightning Jack broke his maiden at Riverton last month.
"I said a few months ago that I think he’s probably the second-best horse I have ever trained," he said.
"He’s just got so much maturing to do but he has tons of ability.
"He had a wee break and freshen up after his last run, as he doesn’t need that much work.
"We were quietly confident, although you never know with a tight, turning track, so you just need a bit of luck.
"It always helps when they are cutting their throats up in front and it worked for us today."
Asano sat off a sizzling early and mid-race speed set by the leader, Miss Federer.
Rider Kylie Williams had the favourite in front soon after the start and they were soon attacked by the second favourite, Burgundy Rose and Doni Prastiyou.
Prastiyou poured the pressure on the leader throughout the race, effectively extinguishing the winning chances of the two leaders.
Runner-up Live Drama was one of the few horses that raced close to that hot speed to figure in the finish.
Rider Terry Moseley had the filly behind Miss Federer throughout, before angling Live Drama to produce what looked to be a winning run.
Only the flying finish of Lightning Jack stopped trainer Lance Robinson winning consecutive Gore Guineas following his victory with Air Max last year.
The result also denied Live Drama’s sire, Otago stallion Ghibellines, his first group or listed race win.
Wild Jack took out Saturday’s Gore Cup for trainer Stephen Blair-Edie and his apprentice Amless Bohorun.
The 7yr-old was unlucky in the Timaru Cup, before being faced with the tough task of leading the chase behind tearaway leader Camino Rocosso in his previous start in the Waikouaiti Cup.
