Arsenal’s English midfielder Theo Walcott (C) celebrates scoring his team’s fifth goal with Arsenal’s Nigerian striker Alex Iwobi (L) and Arsenal’s English midfielder Ainsley Maitland-Niles during the English FA Cup fourth round football match between Southampton and Arsenal at St Mary’s in Southampton, southern England on January 28, 2017. PHOTO: Adrian DENNIS / AFP.

Theo Walcott struck a hat-trick against his former club after Danny Welbeck scored twice on his first start since a knee injury in May as Arsenal thrashed Southampton 5-0 in the fourth round of the FA Cup at St Mary’s on Saturday.

It was a match between two weakened teams, but the strength in depth of Arsenal, FA Cup winners in 2014 and 2015, ensured the visitors won out.
Arsenal manager Arsene Wenger will have been especially pleased with the performance of Welbeck, who had not started since a 2-2 draw away to Manchester City in May.