Whanganui galloper Blood Brotha is out to earn a place in New Zealand racing history in the Auckland Cup, even though the market suggests he won't.

If he wins, Blood Brotha will become the first horse to win the New Zealand, Wellington and Auckland Cups in one season, no mean feat for races which all date back to at least the 1870s.

But to do it he's got to get past Sangster, who was as low as $2 to win the Group One 3200m Auckland Cup at Ellerslie on Wednesday.

The last horse to get close to winning all three was Stipulate, who won the New Zealand Cup and Auckland Cup when the Ellerslie event was run on New Year's Day before running second to Great Sensation when he won his third Wellington Cup in 1963.

Blood Brotha won his second New Zealand Cup (3200m) last November, careering away to win by 6-1/2 lengths, and in late January narrowly won the Wellington Cup (2400m).

"It'd be a pretty big effort if he can pull it off," Blood Brotha's trainer Raymond Connors said.

"He's had a long season obviously and I'm just hoping he can put another big effort in."

Sangster has run into red-hot form in February, winning the International Stakes at weight-for-age over 2000m at Te Rapa and then winning the Avondale Cup (2400m) with 59kg.

Both wins came after his 54.5kg Auckland Cup weight was set, meaning Blood Brotha has to concede him 2.5kg.

"On his last two runs he looks a bit of a home run really, but it's a horse race and everybody's in there with a chance," Connors said.

"He's got to get the distance too I guess, which is probably the only question for him, but he's obviously the class horse of the field."

Blood Brotha, who was fourth favourite for the race at $12 on Tuesday, disappointed when 12th to Sangster in the Avondale Cup but Connors said his horse should enjoy the 3200m.

"We know he can handle the distance so it's just a matter of him running his best. If he does he'll be more than competitive."