Rotherham United marched into the League One play-off places as they won on the road for only the second time this season.
The Millers have been rampant at home but had accumulated only three points on their travels until Richard Wood settled the clash against Rochdale at Spotland in their favour.
It was a deserved victory for Paul Warne's men who created the game's clearest chances and stood up to the home side's physical, niggly approach to climb from eighth to fourth in the table.
Rotherham took the lead in the 57th minute after Dale goalkeeper Josh Lillis had mishandled to concede a corner.
Anthony Forde swung the ball to the back post where centre-half Wood twisted his 6ft 3in frame to head home.
It was the first goal the hosts have conceded in six matches.
Two minutes later, Steven Davies hit the top of the bar with a header for Dale, but Rotherham were threatening a second goal, with Wood this time unable to hit the target with a header.
In driving rain, the Millers should have gone ahead during a purple patch midway through the first half.
Will Vaulks' 21st-minute header looked to be going in until Lillis pushed the ball away for a corner and just two minutes later Richie Towell brought a sharp save from the Rochdale keeper after a superb pass by Darren Potter had opened up the home defence.
Forde had the goal at his mercy as Ryan Williams picked him out in the penalty area in the 26th minute but snatched at his shot.
Davies came closest for Dale before the break, sending a curling half-volley on the turn inches over after 18 minutes.
Dale pressed in the final few minutes, but Rotherham, despite a late scare when Bradden Inman skied a close-range effort over the bar, held on comfortably.
They have now won six of their last eight matches and momentum is building.
Goals: Wood 57 (Rotherham).
Rochdale (4-2-1-3): Lillis; Daniels, McGahey, McNulty, Bunney; Camps (Inman 71) Williams; Rathbone (Andrew 61); Done (Slew 81), Davies, Henderson. Subs not used: Rafferty, Ntlhe, Williams, Moore.
Rotherham (4-1-4-1): O'Donnell; Cummings, Ihiekwe, Wood, Mattock; Potter; Forde (Ajayi 88), Towell, Frecklington (Vaulks 3), Williams; Moore (Clarke-Harris 90+2). Subs not used: Price, Emmanuel, Ball, Yates.
Referee: David Coote (Nottinghamshire).
Attendance: 4,113 (1,221).