Their lead has been reduced to just four points, thanks to Dundalk’s win at Dalymount Park, but Shamrock Rovers will view this one as a point gained.
In between European trips - and just three nights after they banked group stage football - the Hoops held on for a point at the Brandywell to keep hosts Derry City at arm’s length.
The Candystripes, meanwhile, will be kicking themselves over the outcome.
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One missed penalty and a handful of decent chances means the judges’ scorecards would have awarded the points to the Candystripes had it been a boxing match.
Rovers goalkeeper Alan Mannus was definitely the busier of the two goalkeepers and he was well deserving of a clean sheet bonus, presuming there’s one in his contract.
If not, there should have been a whiparound on the bus back to Dublin, where there was no doubt some concern over the injury that forced Graham Burke off early in the second-half.
He frustrated Will Patching from the spot and later on from open play, denied Derry substitute Michael Duffy moments after his arrival and enjoyed a bit of luck too.
Mannus could only watch as Ryan Graydon’s angled effort smacked off the frame of his goal.
It was the visitors that made the most promising start. At one stage they earned four corners in a row.
But that run was ended by a Rory Gaffney header that fizzed wide, while from another flag-kick on 23 minutes, Sean Hoare sent his header glancing outside the right-hand upright.
But as the game settled, both sides managed to cancel each other out, leading to a frustrating stalemate from a neutral perspective.
And then in the 36th minute the game exploded into life thanks to a bizarre incident - and the momentum from then on was largely with the hosts.
As the ball sailed into the area, Farrugia rose at the back post, arms in the air like a Gaelic footballer under a dropping ball.
Why he jumped with both arms aloft was unclear. Was there a push? Did he make contact with the ball? In real time, it looked to have clipped his finger tips.
The Brandywell drew a collective gasp, stunned by the actions of the Rovers man.
And referee Paul McLaughlin seemed paralysed too.
Derry players and fans quickly snapped out of it and the longer things went without a whistle, the louder their protests grew.
After what seemed like an age, McLaughlin pointed to the spot.
But that wasn’t the end of the drama. Patching, usually so proficient from 12 yards, casually strolled up to the ball and rolled it towards the bottom right hand corner.
Unfortunately for the Candystripes star, Mannus guessed correctly and saved with ease.
Mannus received a sterner test moments later when he was forced to tip Patrick McEleney’s half-volley from the edge of the area over his crossbar.
Both Gaffney and Burke tried their luck as half-time approached, but the former fired wide and the latter found the arms of goalkeeper Brian Maher from 25 yards.
Maher was the first keeper to be tested after the break. He got down low to his right to keep out Sean Kavanagh’s strike. The former Fulham man was teed up by Andy Lyons.
The save of the night belonged to Mannus, however, when he dived to his left to deny substitute Duffy moments after his arrival onto the pitch.
Mannus was beaten on 66 minutes when Graydon struck the ball towards goal, but his drive flashed across the keeper and rattled the inside of the post.
The rebound fell kindly to McEleney but his shot was blocked. Loud claims for handball were waved away by McLaughlin.
Derry’s policy of getting the ball to substitute Duffy as often as possible was beginning to pay off, as his runs in from the left channel were causing alarm in the visiting defence.
One shot was blocked rather painfully by Lee Grace, while a second was gathered by Mannus.
Rory Gaffney and Jack Byrne were both off-target at the other end, while sub Aidomo Emakhu’s determined run ended with a shot from distance that didn’t trouble Maher.
Mannus had to be alert on 84 minutes, however, to keep out a Patching snap shot as Derry pushed once again for the winner.
In the remaining minutes, he showcased the calming dominance of his area that has been a hallmark of his European displays this season as Derry, to no avail, flung the ball into the area.
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