On her Women's Super League debut for Arsenal, Olivia Smith needed just one moment of brilliance to show why she became the world's first £1m women's footballer.

Minute-by-minute updates: European champions Arsenal kick-off the new season with the visit of a big-spending London rival. Join Rob Smyth

Chloe Kelly, Stina Blackstenius and Frida Maanum were also on target in Arsenal’s 4-1 victory after London City had given them an early scare