Rochdale are on course for a fourth consecutive win in League Two, with Matthew Lund putting the Lancashire club ahead against struggling Portsmouth.
Despite the hosts coming into the game in better form than their opponents, it was Pompey who threatened early on when Toumani Diagouraga's left-footed strike forced a save out of Josh Lillis.
On seven minutes, Rochdale's defence scrambled to clear Bondz N'Gala's header off the line and Joe Devera was unable to tuck away the rebound for Portsmouth.
However, it was Dale who took the lead when a Rhys Bennett corner wasn't cleared by the visitors' defence and the ball reached Lund, who fired home from close range.
That setback didn't seem to faze Pompey too much as Ricky Holmes brought another stop out of Lillis moments later.
Rochdale were able to weather any pressure and almost doubled their lead just before the half-hour mark when Lund's shot brought a good save from Trevor Carson when the ball seemed destined for the top corner of the net.
As the half drew to a close, the league leaders could have added to their advantage as Lund again threatened, and then Peter Vincenti also went close to finding the back of the net.
