Shelbourne 0 Drogheda United 2 Jason Byrne was sent off as Shelbourne showed a lack of composure they'll not want to repeat against KR Reykjavik come Wednesday's return of their Champions League qualifiers as they lost for the first time at Tolka Park in the league this season.

Byrne, the league's top scorer, was booked for dissent on 37 minutes. He was then shown a straight red card for allegedly making a gesture to assistant referee Tony Ryan in first-half stoppage time. Ryan flagged Cork referee Anthony Buttimer who promptly sent off Byrne.

Shelbourne may also face further censure from the league as their secretary, Ollie Byrne, had to be restrained by his backroom staff from giving his view of the incident to the officials as they left the field for the interval.

Perhaps with Wednesday in mind, Shelbourne adopted a 4-1-4-1 formation, with Jim Crawford sitting in front of the defence and a soon-to-be frustrated Byrne ploughing a lone furrow up front.

While Shelbourne won a fierce midfield battle, they got little change out of the superbly marshalled Drogheda defence, with Steven Gray and full debutant Jermaine Sandvliet particularly impressive.

Drogheda took the lead on 31 minutes with a penalty after Jamie Harris clumsily tripped Declan O'Brien as he ran onto Gary Cronin's ball.

Steve Williams dived the right way to parry away John Lester's poorly-hit spot kick, but the ball ran back kindly into the path of the Drogheda midfielder who drilled home the rebound.

Drogheda got their second on 64 minutes when Cronin chipped Williams brilliantly.

SHELBOURNE: Williams; Heary, Rogers, Harris, Crawley; Crawford (Hoolahan, 41 mins); Cawley (Rowe, h/t), Moore (Morgan, 79 mins), S Byrne, Cahill; J Byrne.

DROGHEDA UNITED: Rogers; Flanagan, O'Connor, Gray, Sandvliet; Whelan, Lester, Molloy, Cronin; O'Brien (Lynch, 90 mins), Rooney (Freeman, 71 mins).

Referee: A Buttimer (Cork).