Gary Jones's stoppage-time penalty was enough to beat Bournemouth and move Rochdale off the bottom of the League One table.
The Cherries' Stephen Purches was stretchered off with a serious leg injury in the first half.
Wes Thomas and Matt Tubbs went close for the visitors, while Jones and Kevin Long forced saves from Darryl Flahavan.
The game looked destined for a draw until Dan Strugnell pushed Joe Thompson, leaving Jones to lash home.
Rochdale have now won two games on the bounce, but remain four points from safety.
Bournemouth missed an opportunity to close in on the play-off places, and stay four points adrift of sixth-placed Stevenage having played four more games.
VIEWS FROM THE DRESSING ROOM
Rochdale manager John Coleman told BBC Radio Manchester:
"I think on the balance of play we just about deserved to win.
"We said to the lads we've got to keep knocking on the door and eventually it will open for us and it did, albeit so late.
"I think in the three games we've played we've defended really well but we've got a lot of games to go we've got to defend well in.
"We've got a long, long way to go and every game we play from now until the end of the season is going to be difficult."
Lee Bradbury tells BBC Radio Solent Sport:
"I think we should have at least had a point out of the game. But I looked at the penalty decision and I think it's a penalty.
"The most disappointing thing is coming here and getting anything. We rolled our sleeves up for periods of the game but not the whole game.
"It's going to be difficult with teams above us with games in hand - we're relying on them to slip up.
"You have got to go to the hard places and get results."
Rochdale 01 Kurucz 02 Darby 03 Widdowson 05 Amankwaah 12 Long 06 Barry-Murphy 07 Kennedy 08 Jones 10 Grimes Booked 11 Adams (Jordan - 90' ) 26 Akpa Akpro (Thompson - 75' ) Substitutes 23 Lucas 17 Holden 22 Jordan 15 Thompson 16 Tutte Bournemouth 23 Flahavan 11 Daniels 18 Francis Booked 19 Purches (Strugnell - 13' ) 40 Zubar 07 Pugh 08 Arter Booked 16 MacDonald 32 McDermott (Fletcher - 86' ) 09 Thomas 25 Tubbs (Malone - 85' ) Substitutes 22 Malone 31 Strugnell 15 Gregory 29 Stockley 33 Fletcher