Danny Graham scored late on as promotion-chasing Blackburn snatched a 1-1 draw against Northampton at Ewood Park. John-Joe O'Toole's 12th-minute glancing header looked to have ended Blackburn's 16-match unbeaten Sky Bet League One run but Graham nodded in an equaliser in the 74th minute. However, Rovers could not force a winner and slipped out of the top two following Shrewsbury's win at Portsmouth. Despite dominating the opening exchanges, Blackburn were caught with a Northampton counter-attack when Joe Bunney crossed for O'Toole to deftly nod in his fourth goal in his last four games.Craig Conway came closest to a first-half equaliser after reacting quickest to a corner but his shot whistled just wide.Northampton perhaps should have had a second after the break, only for Regan Poole to volley over.And they paid the price when Dominic Samuel floated a cross in for Graham to head his 10th goal of the season into the bottom corner.Bradley Dack was denied a winner late on when Richard O'Donnell superbly parried his late strike, as the Cobblers moved three points away from the drop zone.