Tom McGlinchey has stepped down after four years as manager of the Waterford senior footballers.
McGrath led Waterford to a McGrath Cup win in 2015 and this year's the county secured a first Championship win since 2011 over Wexford.
They came close to knocking Cork out of the Munster Championship
McGlinchey said at the time of their win this summer: "We try so hard. We know we're in Division 4 and understand that, we wouldn't be considered one of the top teams.
"Over the last number of years we haven't had the reward. We've been close. Last year against Cork we were close.
"Some of the lads involved against Galway a couple of years ago were close to getting that elusive win and a Championship win away to a Division 3 team is absolutely fantastic. The odds were totally against us."
Waterford have yet to comment on who will replace the outgoing manager.
Guckian was appointed on a two-year term in Leitrim, with the defeat to the Farney in Round 3 of the qualifiers being his last game at the helm.
The Carrrick-on-Shannon native was keen to stay on and was making plans for 2019 but he was told by the county board that he would have to reapply for his job.
