Dimitar Berbatov netted the game's only goal in the 52nd minute when he converted Riether's low right-wing cross.
London: Tottenham Hotspur's challenge for a Champions League place received another setback on Sunday when they lost 1-0 at home to Fulham to register a second consecutive Premier League defeat.
Story first published on: Sunday, 17 March 2013 23:05
Having eliminated Inter Milan from the Europa League on Thursday, Spurs were bidding to tighten their grip on third place in the table and Gareth Bale had an early header cleared off the line by Sascha Riether.
However, the hosts lost Michael Dawson to injury at half-time and then saw former striker Dimitar Berbatov claim the game's only goal in the 52nd minute when he converted Riether's low right-wing cross.
Spurs' best chance fell to Jermain Defoe in the dying stages, but his effort from Bale's cut-back met its match in a superb reflex save from Mark Schwarzer.
Coming in the wake of last weekend's 3-2 loss at Liverpool, Spurs' defeat left them vulnerable to attack from fourth-place Chelsea, who can claim third place if they overcome West Ham United at Stamford Bridge later on Sunday.
Earlier, Sunderland failed to capitalise on the dismissal of Norwich City goalkeeper Mark Bunn as they were held to a 1-1 draw at the Stadium of Light.
After Wes Hoolahan headed Norwich in front in the 26th minute, the visitors lost Bunn to a straight red card when he handled the ball outside his area.
Craig Gardner levelled for Sunderland with a 40th-minute penalty after a handball by Sebastien Bassong, but Sunderland could find no way past the visitors' 10 men in the second half.
The draw left Sunderland seven points above the relegation zone after their seventh game without a win, while Norwich jump two places to 12th in the Premier League standings.
In the day's other game, third-bottom Wigan Athletic can close to within three points of safety if they defeat Newcastle United at the DW Stadium.