Alfie Sullock: Michael Pearce 'can't explain' injuries
A man accused of beating a baby to death has told a court he does not know how the six-week-old suffered brain damage and bruising to his body.
The injuries to Alfie Sullock were said to have happened in the two hours Michael Pearce was babysitting on 16 August last year in Cardiff.
But the defendant told Newport Crown Court he did not do anything to hurt the baby.
Mr Pearce, 32, of Nelson, Caerphilly county, denies murder and manslaughter.
Giving evidence on Wednesday, he told jurors he left the room Alfie was in for "no more than 30 seconds" and when he came back, he "looked over at Alfie and couldn't see his chest going up and down and presumed he wasn't breathing".
He then said he "went over to him and checked for a pulse on the side of his neck", before administering mouth to mouth to Alfie.
He said he had learned the technique during his Duke of Edinburgh award in school.
Two paramedics arrived four minutes after Mr Pearce called 999 and took Alfie to hospital.
The court was told that a series of photos taken at the hospital showed "obvious bruising on his face", but the defendant said he did not see that.
Asked if he could explain anything that caused that bruising, he replied: "I can't explain it."
Mr Pearce denied slapping or shaking the baby, saying: "I didn't pick up anything and didn't do anything."
He denied hitting Alfie with a bottle or shoes, but admitted prodding him in the chest when administering cardiopulmonary resuscitation (CPR).
The court has previously heard that the defendant and Alfie's mother, Donna Sullock, became friends when she was six months pregnant and she had no issues leaving her baby with him when she went out for the first time since giving birth.
The 29-year-old said her son had no marks on him when she left and jurors heard the defendant text her saying Alfie was "fine" but soon after he was brain damaged.
It is claimed the baby was beaten with a shoe or sandal and the bottom of a plastic bottle.
The trial continues.