The Republic of Ireland international volleyed home a cross from Darren Bent – who had missed a glorious chance to level on the hour mark – to keep Tottenham's unbeaten run in the Premier League going.
Kieran Richardson needed just three minutes to open the scoring for Sunderland while Keane registered for the visitors with less than 60 seconds left on the clock to add to his excellent display in Tottenham's victory over Middlesbrough during the week.
Richardson slotted calmly past goalkeeper Heurelho Gomes after latching on to a loose ball to give his side the perfect start.
However, Spurs might have been level 11 minutes before the break had keeper Marton Fulop not saved bravely from Ledley King after Jermaine Jenas' free kick had been blocked.
Both sides still need the points that will secure their Premier league survival, but on this evidence neither side deserves to face the drop, with endeavour and invention coming from both teams.
Both Harry Redknapp and Ricky Sbagria would have been content with a share of the spoils beforehand, though the late nature of Tottenham's equaliser will leave the visiting manager in much the better mood tonight.
The result was fair on both teams with nothing to chose between them on the pitch or, still, in terms of Premier League points.
Both will continue to look nervously over their shoulders until safety is confirmed but will welcome another point to put towards that aim.