However, Waller said there was only a slim chance of the mare starting in the All-Star Mile, with the race he is after being the Group 1 Australian Cup (2000m) at Flemington on March 30.
"She'll stay down there and run in the Australian Cup. That's the race she's been set for," Waller told Channel 7.
"It's unlikely she'll run in the All-Star Mile because I didn't think she got around Caulfield that well. We won't say no, but I think it's the Australian Cup."
Atishu beat only one runner home when eighth behind Mr Brightside in the Group 1 C F Orr Stakes (1400m) at Caulfield on February 10 when resuming and Waller took the mare back to Sydney in a bid to turn around the mare's fortunes.
The tactic worked as Atishu rode the speed and held off a late flurry of rivals under Blake Shinn .
Sent out the $4 favourite, Atishu scored a three-quarter length win from Holymanz ($12) with the unlucky Ayrton ($7) a head away third.
Shinn said Atishu was in for a good preparation, adding he was grateful for getting the opportunity to partner with the six-year-old.
"These mares are wonderful to ride when you can get a chance to ride them and they're just different level," Shinn said.
"They've got a great will to win and even when she ran second to Pride Of Jenni in that mare's mile (Empire Rose) here, I just loved her grit.
"I could see that today and felt that riding her, she was never going to lose and the more I asked her the more she responded.
"She's a lovely mare and is in for a great prep and hopefully I can stay with her now."