Leyton Orient have come from behind to reach half-time ahead against a Rochdale team who will have to play the remainder of the game with 10 men.
Matt Done almost gave Dale the lead inside the opening 60 seconds, but his shot from the centre of the box was blocked.
The midfielder wouldn't be denied on four minutes when his effort from the edge of the area nestled in the bottom corner of The O's net.
Rochdale, looking for a fourth win in five league games, continued to show attacking intent and had an opportunity to retake the lead on 20 minutes, but Peter Vincenti was unable to keep his header down following a corner.
Keith Hill's side were dealt a blow on the half-hour mark when Ashley Eastham was sent off for his challenge on Darius Henderson in the penalty area. Chris Dagnall was unable to capitalise as Logan was able to reach down to his left and tip the spot kick away.
However, with half time approaching, Romain Vincelot was able to breach the Rochdale defence with a close-range header from Henderson's cross.