Son had scored twice on his home debut in Tottenham's Europa League victory against Qarabag of Azerbaijan on Thursday and the forward's dream start continued as he was the toast of White Hart Lane just three days later.
The 23-year-old settled a hard-fought encounter midway through the second half to give Mauricio Pochettino's side their first home league win of the season.
Son already has three goals in three appearances since signing from German club Bayer Leverkusen for £18 million ($27 million, 24 million euros) in August and he departed to a standing ovation with 12 minutes remaining.
After his team made a slow start to the season, Son's dynamic displays have been a much-needed tonic for Tottenham, helping them climb to mid-table in the Premier League with two successive wins.
Pochettino made five changes to the side which beat Qarabag, including a return for Harry Kane after the out-of-form England striker was rested for the Europa League tie.
Kane's presence up front meant Son moved into a deeper role, but he was no less effective as he roamed menacingly across Tottenham's attacking midfield trio.
Kane, without a club goal this season, hadn't scored at White Hart Lane since March and the youngster's lack of confidence was clear to see when he headed over from a corner in the opening minutes.
While Kane struggles to find his peak form, teenage midfielder Dele Alli has burst into the Tottenham team in the vibrant manner that his team-mate did last season.
