Sunderland dropped to the foot of the Premier League table as Ryan Mason's 82nd-minute goal provided Tottenham with their first win of the season.
Jermain Defoe, playing against his former club, wasted the best chance in the first half. He was sent through on goal by Jeremain Lens but his shot came back off the post.
Harry Kane failed to connect when found unmarked at the back post, and the game appeared to be headed for stalemate. The England international, who scored against both San Marino and Switzerland last week, has yet to net for Spurs this campaign.