Late goals from Stephen O’Donnell and John Mountney gave Dundalk a deserved victory at Tolka Park as Shelbourne finished with ten men once again.
Dundalk skipper O’Donnell struck on 87 minutes to loop a header over Niall Burdon in the Shelbourne goal from Darren Meenan’s deflected cross to put Dundalk ahead for the first time on the night.
Substitute Mountney then added a third three minutes into stoppage time when robbing Ian Ryan to slide the ball past Burdon.
Shelbourne, who had Paul Crowley sent off in last week’s defeat in Bray, had skipper Graham Gartland dismissed for a second booking following a foul on O’Donnell four minutes before Dundalk went ahead.
In truth, Dundalk might have won by more as the crossbar had deprived Richie Towell’s stunning long range drive in the 80th minute.
Shelbourne had snatched the lead against the run of play on 43 minutes.
Hughes had just failed to make decent contact on a cross from Seán Brennan before Mark Leech whipped over another delivery from the right for Dean Kelly to score with a diving header.
Dundalk goalkeeper Peter Cherrie brilliantly tipped over Hughes’s curling shot to prevent Shelbourne doubling their lead on 53 minutes.
Two minute later Dundalk got back into the game.
Ryan was booked for hauling down Keith Ward in the box and John Dillon calmly sent Burdon the wrong way from the penalty spot.