Mr Walker, 18, was by the police with stab wounds in Gledwood Gardens, Hayes , near the junction with Gledwood Drive.
Idris Hassan, of Gledwood Gardens, appeared in custody at Wimbledon Magistrates' Court charged with the killing of Mr Walker.
The victim was treated by paramedics for his injuries but they were unable to save him, and sadly Mr Walker was pronounced dead shortly before 4.40pm.
One witness described how she had seen Mr Walker lying in the street covered in blood with his shirt off.
The tragic incident came less then two weeks after a young man was stabbed multiple times in Uxbridge town centre.
There have been three arrests made in connection with Mr Walker's death .
Hassan has been sent to trial at the Central Criminal Court with the next hearing set to take place on Friday (August 19).