Failure to deal with crosses proved to be Finn Harps' undoing in Ballybofey on Saturday night as a rampant Shamrock Rovers cruised into the next round thanks to three first-half goals.

The visitors got off to a great start when Tony Grant rose unchallenged in the box in the fourth minute to head in Shane Robinson's corner, and after that they were more or less in control of the game.

Harps might have got back on level terms in the eighth minute when caretaker boss Jonathan Speak prodded a cross from Paddy McGrenaghan towards goal.

But his effort, typical of the kind of luck his side have been having all season, came off the base of the post. And there was worse to follow for Harps when Rovers increased their lead in the 25th minute. This time it was Brian Byrne who had all the time in the world to pick his spot with a header. His first effort bounced off the ground and was tipped on to the bar by Gareth Downey, but he had the simple task of heading in the rebound from close range.

Harps at that stage appeared to throw in the towel and it was no surprise when Rovers added a third four minutes later. Once again a Shane Robinson corner caused the damage and Pat Deans headed into the roof of the net past the stunned home defence.

Paddy McGrenaghan, who was Harps' most effective player, set up Don Tierney in the 43rd minute but his shot was blocked and the visitors went into the break with a comfortable three-goal advantage. Having thrown away a similar lead last week against Bohemians, Rovers were given a slight scare seconds after the restart when Fergal Harkins' shot clipped the crossbar.

However, while Harps upped their game in the second half they rarely looked like scoring. Their best chance came in the 61st minute when Jonathan Minnock's effort hit referee John Stacey and fell to Speak inside the box, but his shot was blocked by the alert Rovers defence.

At the other end Tony Grant had penalty claims overlooked in the 73rd minute when he seemed to be hauled down inside the box by Minnock.

Grant might have scored again in the final seconds when he was denied by Downey, but he wasn't too perturbed by the miss as his side eased their way into the next round leaving Harps with nothing to look forward to but a relegation battle.

FINN HARPS: Downey, R Kenny, Minnock, Fitzhenry, Bradley, McGrenaghan, Mohan, Tierney, Speake, J Kenny, Harkin. Subs: McHugh for R Kenny (60 mins).

SHAMROCK ROVERS: Horgan, Vaudequin, Woods, Cronin, Palmer, Colwell, Deanes, Robinson, Francis, Grant, Byrne. Subs: Kavanagh for Robinson (88 mins).

Referee: J Stacey (Athlone).