A Paul McLaren own goal gifted struggling Brighton the win that gave their survival hopes a massive boost.
The Rotherham midfielder headed past his own keeper and sent 2,500 travelling fans cheering all the way back to the South Coast.
It left Millers boss Mick Harford still looking for his first win and the Yorkshire side without a Saturday home victory all season.
Brighton made a nervous start and when the breakthrough came it was thanks to a huge slice of good fortune.
Richard Carpenter fired a free-kick into the area after 19 minutes and McLaren reached it at the near post but glanced the header past his own keeper.
Gary Hart might have added a second after he tore into the area but Chris Swailes halted him with a tremendous tackle before keeper Mike Pollitt saved at the feet of Chris McPhee.
Brighton's luck held out seconds before half-time when Shaun Barker powered a header from McLaren's corner that beat Alan Blayney but scraped the bar on its way over.
Rotherham could have levelled a minute after the restart but Blayney turned away a goalbound header from John Mullin before Rob Scott headed wide.
Brighton should have put the game beyond Rotherham in a hectic late spell.
First Dean Hammond looked certain to seal the win but prodded a shot against the post from eight yards and then Leon Knight struck a blistering rising shot that beat Pollitt but cannoned against the bar.
But the woodwork worked in Brighton's favour at the other end when a Barker header hit the post.
The Rotherham midfielder headed past his own keeper and sent 2,500 travelling fans cheering all the way back to the South Coast.
It left Millers boss Mick Harford still looking for his first win and the Yorkshire side without a Saturday home victory all season.
Brighton made a nervous start and when the breakthrough came it was thanks to a huge slice of good fortune.
Richard Carpenter fired a free-kick into the area after 19 minutes and McLaren reached it at the near post but glanced the header past his own keeper.
Gary Hart might have added a second after he tore into the area but Chris Swailes halted him with a tremendous tackle before keeper Mike Pollitt saved at the feet of Chris McPhee.
Brighton's luck held out seconds before half-time when Shaun Barker powered a header from McLaren's corner that beat Alan Blayney but scraped the bar on its way over.
Rotherham could have levelled a minute after the restart but Blayney turned away a goalbound header from John Mullin before Rob Scott headed wide.
Brighton should have put the game beyond Rotherham in a hectic late spell.
First Dean Hammond looked certain to seal the win but prodded a shot against the post from eight yards and then Leon Knight struck a blistering rising shot that beat Pollitt but cannoned against the bar.
But the woodwork worked in Brighton's favour at the other end when a Barker header hit the post.