Still the most competitive of the Dublin derbies, this was as unpredictable as any that have gone before as Bohemians's second-half powerplay brought its reward of a deserved equaliser at Tolka Park.
But how Roddy Collins's side didn't take much more from this game as they fight to steer clear of the relegation zone was mystifying, though a superb display of goalkeeping from Tony O'Dowd provided some of the answers.
Bohemians passed the ball well early on with Paul Byrne instrumental in much of what they tried to do. But there was no substance to their probings, with Byrne's frustration leading to several long-range attempts which were well wide of O'Dowd's goal.
Rovers soon settled and their far more direct approach soon brought its reward. Jason Sherlock came close twice before he eventually scored after 37 minutes.
Bohemians weren't defending well and paid when they failed to clear a Billy Woods corner. Shaun Maher's feeble headed clearance was pounced on by Sherlock who scored with a spectacular overhead bicycle kick from six yards.
Bohemians laid virtual siege to the Rovers goal in the early stages of the second half.
A Byrne corner caused a scramble with Brian Mooney's back-post shot deflected out for another corner. O'Dowd then saved from Graham Lawlor before Gino Brazil cleared off the line from Maher. O'Dowd again had to save well from a Mullen header on 63 minutes. The Bohemians blitz was rewarded on 64 minutes when Mooney's deep cross to the back post was headed powerfully past O'Dowd by captain Tony O'Connor.
Rovers almost provided an unlikely twist late on when Tracey weaved through to shoot; Dempsey producing a magnificent one-handed save.
SHAMROCK ROVERS: O'Dowd; Britton, Brazil, Palmer, Woods; Tracey, Colwell, Murray, Morrisroe; Sherlock, O'Neill. Subs: Kenny and O'Meara for Morrisroe and Murray (both 69 mins); O'Connor for O'Neill (78 mins).
BOHEMIANS: Dempsey; O'Connor, Maher, O'Driscoll, Fairclough; P Byrne, O'Hanlon, Mullen, Brunton; Swan, Lawlor. Subs: Mooney for Fairclough (36 mins).
Referee: H Byrne (Dublin).