It's now a three-horse race for promotion after a Tony Izzi volleyed goal after just five minutes gave Dundalk a scarcely-deserved 1-0 win over Kilkenny City at Oriel Park on Saturday night.
Izzi finished from close range after Anton Reilly failed to connect properly with Noel Melvin's long ball into the Kilkenny area.
Thereafter, it was all Kilkenny, who were unfortunate not to have been level by the interval.
Dundalk came more into it in the second half and only a brilliant save by Robbie Forde denied Izzi a second goal.
The win leaves Dundalk just one point behind joint leaders Longford and Bray, with Kilkenny now nine points adrift and surely out of contention.
An own goal by Glen Smart gave Home Farm/Fingal a seventh-minute lead on their way to a 2-1 defeat of St Francis in a tempestuous game at Whitehall.