Wilson Waweru scored the only goal of the match
Shane Keegan's side were 1-nil winners away to Wexford last night.
Ronan Coughlan's 33rd goal of the season gave Waterford the lead away to Athlone, but they had to settle for a 1-1 draw.
Both second legs will be played on Saturday.

Two Injuries And Possible Suspensions For Ireland Ahead Of Saturday's Game With Japan
Lunchtime Sports Update
FloMAX Liffey Celtics Secure First Win In Domino's Women's Super League
Monday Morning Sports Update
Sunday Mornings Sports Update
Grangenolvin And Sallins Victories In The Leinster Club Championship Yesterday
Friday Evening Golf Update
Former Dublin Player Jason Sherlock Joins Roscommon Management Team