Wojciech Tadewicz, 27 of Whittington Avenue, Hayes, was found guilty of the murder of Sandra Zmijan after a trial at the Old Bailey.
A jury returned a unanimous guilty verdict on 5 December. Tadewicz will be sentenced at the same court on Friday, 6 December.
The court heard how Sandra, a 31-year-old mother of two, went to Tadewicz’s home address on Thursday 20 September, 2018, to pick up a ticket from him to an amateur boxing event. Sandra was to compete in a charity boxing match the following day, as she had recovered from cancer and taken up boxing as a hobby.
The pair had been in a six-month relationship but Sandra had texted Tadewicz a few days before to tell him she just wanted to be friends.
Analysis of CCTV and Oyster card records carried out by detectives from the Met’s Homicide Team, revealed that Sandra had travelled to Tadewicz’s address on 20 September, but had not returned home to her two children.
Emergency services were called to Tadewicz’s address in the early hours of Friday, 21 September, 2018, after his housemates found him in his room with multiple cuts to his wrists and arms.
Tadewicz was taken to hospital and spoken to by police officers. He said he had smoked cannabis the night before and did not remember how he had got cut.
After Sandra failed to return home for two nights, she was reported missing on Saturday, 22 September, 2018.
Sandra’s children and friends had tried to find her and had called her constantly over four days. On Monday 24 September some of Sandra’s friends, along with her daughter, rang her phone again and this time it was answered by Tadewicz’s sister who had found the phone in Tadewicz’s room.
Police were called to the Whittington Avenue address again shortly before 10am on Monday, 24 September and, after a search behind trees in the back garden, they found Sandra’s body.
A claw hammer stained with Sandra’s blood was found next to her.
A post-mortem examination gave a cause of death as head injury through a sustained assault with a heavy blunt object.
Tadewicz was arrested at hospital on 24 September and gave a series of ‘no comment’ police interviews. He was charged with murder two days later.