Shamrock Rovers' lead at the Premier Division summit could slip to two points on Saturday night after another Dublin derby blank.
Sunday's scoreless draw in Inchicore saw the Hoops drop points for the first time this term - and there were parallels in Tallaght tonight as Stephen Bradley's side lorded it in the first half hour.
But they failed to capitalise and, with Rory Gaffney's injury reducing them to 10 men in the closing stages, Rovers had to be composed to see it out for a draw.
On the back foot for the most part, Shels did graft a couple of chances and could have left with a smash and grab victory.
And as predicted by Reds boss Ian Morris, the lack of a big home crowd because of the current restrictions didn't help Rovers when they needed to push on.
Shels' northside rivals Bohs will be happy enough with the Reds' night work. The closest side to Rovers can move to within striking distance tomorrow.
It looked really promising for Rovers early on and Colin McCabe did well to stop Graham Burke's stinging effort.
Soon after, Neil Farrugia's dangerous near post ball looked destined for a Burke tap-in, but Dan Byrne intervened in time.
From the corner, McCabe made a point-blank save from Aaron McEneff.
Rovers attacked incessantly and Shels had to dig in, with the hosts repeatedly looking to use Neil Farrugia's pace down the left.
Farrugia found Burke in the box but McCabe was again equal to his effort.
In the 28th minute, a flick by Aaron Greene cannoned wide off team-mate Roberto Lopes.
Then Jack Byrne, who will hope to be included in Stephen Kenny's first Ireland squad on Monday, collected the ball on the left touchline and danced away from three challenges - but again without the necessary killer end product.
Shels were then gifted a chance out of nowhere with eight minutes of the half remaining.
Georgie Poynton's deep cross was lost in the air by Alan Mannus, whose fumble to Dayle Rooney had Reds forwards Kilduff and Ryan Brennan screaming for a centre.
Instead, the winger went for glory as Mannus scrambled to recover and his shot from an acute angle blazed over.
Mannus was hesitant again soon after as he failed to properly deal with a Rooney cross, but Rovers cleared, and the half ended with Kilduff's shot on the turn dropping into the arms of the Hoops keeper.
Rovers' frustration grew as they dominated possession in the third quarter without really threatening, before the contest really opened up and when Rooney fed sub Jaze Kabia, he needed to do better than blaze over.
In response, Greene was denied by the ever-vigilant McCabe.
The loss of Gaffney with 15 minutes to go - he had replaced Joey O'Brien on 68 minutes - left Rovers down a man as they were unable to bring on another sub having used their three intervals.
It made it a nervy finish for them, another point gained but two more lost.
Shamrock Rovers: A Mannus; O'Brien (Gaffney 65), Lopes, O'Brien; Finn (Marshall 59), O'Neill, McEneff, Farrugia (Williams 74); Byrne; Burke (Watts 74), Greene.
Shelbourne: McCabe; Poynton, D Byrne, L Byrne, O'Hanlon; Farrell (Kabia 65), Deegan, Quinn, Rooney; Brennan (Dobbs 83), Kildfuff (M Byrne 83).
