The 25-year-old laid on a key pass into the box for Wayne Routledge to shoot past Hugo Lloris early in the first half.
It was his first assist in seven games (three starts) since moving from Aston Villa on transfer deadline day in January.
Manager Paul Clement was rewarded for his decision to start the Ghanaian when he raced into the Spurs back end and cut back to give Routledge the pass that sent them into the lead.
However, title hopefuls Tottenham kept fighting till the end and were rewarded with a Dele Alli equalizer on 88 minutes.
With seven minutes of injury time granted by the referee, Heung-Min Son scored the go-ahead goal for the visitors one minute into added time.
Christian Eriksen added the coup de grace three minutes later to complete a famous comeback for Tottenham who kept their hold on second place and pressure on leaders Chelsea.The Blues had to fight hard to see off the challenge of Manchester City at Stamford Bridge, winning 2-1