When he returned to check on her he found her on the floor screaming "but not as loud as her normal scream when she wanted attention."
He had not seen any injuries except a red line on top of her lip which did not look fresh.
Maija vomited after each bottle he gave her making him think she must have eaten something during the day that upset her stomach, Duff told the detective interviewing him
He said he had attempted unsuccessfully to text and call Puhi.
That night he'd been up and down before falling into a deep sleep with the baby on the couch, waking to find Maija still in the same position with phlegm on her mouth which he sucked out and blown through her nose.
"I couldn't hear a heartbeat, I knew she was gone but [I was] trying to tell myself she hadn't gone'"
Asked about Puhi's reaction when he told her about the baby he responded "there was no reaction"
Questioned about possible previous injuries Duff said about two weeks before Maija died he'd unstrapped her from a walker, forgot he'd done so and while carrying her down steps she'd fallen face first onto the pavement. Her forehead bled but quickly scabbed over.
Asked about finding Maija seemingly lifeless Duff replied: "My gut feeling was I had I effing squashed her again or yeah, was it the fall? I was thinking all sorts, it was like f*** I'm coming to the realisation she's gone and trying to tell myself she isn't gone."
Duff revealed the baby had previously fallen from the couch but denied ever using excessive force against her although he admitted picking her up by the wrists when he became sick of her crying, and shaking her at times out of frustration "but not with excessive force".
Earlier in the day the court heard ambulance officer Jeremy Ross testify that he didn't see any signs of injury on the infant but there was a little blood under her nose.
Her grandfather had briefly helped with the CPR while he prepared defibrillation pads but because Maija didn't have any heart rhythm these couldn't be used. He continued CPR for another 15 minutes until an intensive care paramedic arrived and confirmed the baby was dead.
That now retired paramedic, Helen Manning, outlined how she'd looked for clues on baby Maija's body that might indicate how she'd died but couldn't find any.
She assured Duff's lawyer Moana Dorset that that included not uncovering any marks on the back of the infant's head.
She agreed whanau members had gathered around the ambulance praying as the baby was being worked on.
Amber Anderson testified Maija's mum, Melina Puhi, stayed with her at Lake Rotoaira the night before the baby's passing. When Puhi received a text early the next morning indicating her baby was sick, she'd driven her distraught friend to Turangi.
Probed by assistant defence lawyer Rebekah Webby, she described both Puhi and Duff as being very upset and comforting each other.
Duff's sister, Jessica Haewera, outlined how Duff turned up at her home early on March 12 crying "hard out" and sobbing that "baby has gone".
The trial continues.
