He is a home bred, still owned by breeder Hec McCallum, and didn't race until April of his three-year-old season.
"Back when Avantage was winning those juvenile races our fella still couldn't see over the stable door," says Tavi Mac's trainer Allan Sharrock.
Even when Tavi Mac improved every start last season and kept on winning, any future comparison with Avantage seemed unfair.
That changed in the Group 2 Foxbridge Plate at Te Rapa on September 5 when Tavi Mac, across the field from barrier 14, worked the hardest in the race and went down by a length to Avantage, and she took most of the straight to get past him.
The little equine sausage dog had arrived in the big time and that gets even bigger, with the Telegraph at Trentham one of New Zealand's iconic races.
So the question on the mind of Sharrock, and plenty of punters, too, is how much has that once-wide gap closed in the four months since Te Rapa?
"I am sure it has closed quite a bit," says Sharrock. "Our horse has learned to race and how to conserve more energy in a race.
"He is a proper Group 1 horse now, judging by how he beat Callsign Mav last start and while 1400m is probably his better distance the Telegraph (1200m) often races like a 1400m."
As for Tavi Mac being relatively unproven at weight-for-age, a scale ideally suited to Avantage, Sharrock says now his star is a rating 105 horse, weight-for-age works for him, too.
"I think he can win," he says.
"He is very, very well, he couldn't be better. And it is not as strong a field as some years.
"He has a perfect draw to sit just off the speed and I think there might not be a lot between him and Avantage for the whole race. But she is a bloody good mare. So we will find out this weekend how much that gap has closed."
Avantage is coming off a clinical win in the Railway at Ellerslie and won this race second-up last year, also coming from a wide barrier, so there is no reason she can't do it again.
It is hard to make a case for most of the opposition beating her, with the three exceptions of Tavi Mac, two-time Telegraph winner Enzo's Lad, and Spring Heat, who was third in this race last season and luckless in the Railway.
Avantage faces having to travel wide across the Trentham dogleg and if the leaders kick hard at the 400m those who take the short odds on Avantage might be in for some uncomfortable moments.
She is a hell of a mare and is clearly the one to beat but there are going to be better $1.65 chances racing in the weeks ahead because of the class of horses she is going to have to run past.
There will be plenty of punters willing to take the short odds, even in a multi with stablemate Brando in the Levin Classic, but purely based on price, Avantage may be more fun to watch than to back.
Sharrock's Trentham summary
Sharrock hopes to win the Telegraph at Trentham with Tavi Mac, but he also takes three other good chances to the meeting.
Here is how the man who sits third on the trainers' premiership with a winner every 3.88 starts sums up his other hopes.
1. Waisake (R2, No 1): "He is a natural stayer who we have been trying to peak for the Wellington Cup in two weeks.
"He is well and gets a 2kg claim with Hazel [Shofer] on so he has to be hard to beat, not only this week but I think he can win the Cup, too."
2. Sinarahma (R5, No 4): "She is a good mare and ran some of the fastest sectionals in the Cal Isuzu at Te Rapa last start and that was weight-for-age.
"She drops down to 53kg this weekend and that makes her the one to beat. She is a top chance."
3. Our Hail Mary (R7, No 9): "I really like this mare and she is only getting better. What I don't like so much is the set weights and penalties for this race because she is rating 82 and is only getting 2kg from a rating 102 horse like Dolcetto. She can still win but she is not well weighted."