"We just think she didn't like the synthetic track and getting the sand kicked back into her face.
"It looked like she just said, 'no, this ain't for me' and didn't try but we can only put that down to the track, so she will trial again at Te Rapa on the turf in two weeks and that will give us a better idea where she is at."
While Entrieviere had a lacklustre day at the office, her potential successor as Te Akau's glamour girl Imperatriz was enormously impressive winning her heat.
Not only was she the fastest 950m trial winner of the day and the only one to break 54 seconds, but she did so carrying Opie Bosson, who just back from an overseas holiday is weighing well over 60kg.
"With Opie not at his riding weight yet and adding the saddle, she has carried a fair bit of weight," said Walker. "She trialled really well and is a total pro. She is just a very good horse."
Walker was so happy with the trial, he is considering sending Imperatriz to Ruakaka on August 6 for the open 1100m there, but stopped short of confirming she will contest the first Group 1 of the season, the $300,000 Tarzino Trophy at Hastings on September 10.
That could be a crucial warning for punters, as Imperatriz is the $4 futures favourite for the Tarzino, ahead of Entriviere at $7.
"I am pretty sure she will go to Ruakaka and then we will start looking around at her options and the weather, which could play a big part.
"And of course there is Australia to think about, and any win over there adds so much to their value, so we have to consider that. I am sure she will race in Australia at some stage but we aren't committed to anything here yet," said Walker.
With La Crique on the third line of favouritism for the Tarzino but also a huge chance to go to Australia, the 1400m Group 1 looks a risky one for punters, although that is partially mitigated by the TAB's Future Proof guarantee which sees a $50 bonus bet refund if a horse backed in futures markets doesn't start the race.
Walker was happy with many of the huge team who trialled yesterday, including some of those who finished midfield or worse because they were not ready to be pressured.
"There are plenty of smart horses there and punters should watch out for Bubbles Await, who is a nice juvenile by Almanzor," said Walker.
Just as happy but with far smaller numbers was fellow Matamata trainer Andrew Scott, who liked what he saw from Dragon Leap in his 950m heat.
"We've had all sorts of problems with his feet in the last year but they are good as gold now and he is a different horse," said Scott.
"So he will go to the 1100m at Ruakaka, then the Foxbridge [Te Rapa, August 27] and the Tarzino.
"We're quite keen on the first two legs of the Triple Crown at Hastings before we commit to the last leg."