THE Airtricity League promotion/ relegation play-off tie is on a knife edge going into Friday's second leg at the RSC after Stephen McDonnell's 75th-minute strike secured a draw for 10-man Dundalk at Oriel Park.
Buoyed by a run of 11 straight wins on the road, Waterford impressed in an action-packed first half, forcing Dundalk goalkeeper Peter Cherrie into a number of saves.
However, it was the hosts who drew first blood as Stephen Maher set Chris Reilly away on the left and he cut the ball back for Lorcan Shannon to fire home on 22 minutes.
Waterford almost replied straight from the kick-off. Sean Maguire cut through the Dundalk back-four to set up Paul Phelan but Cherrie did brilliantly to tip over.
Dundalk were dealt a hammer blow after 33 minutes when Maher received a straight red card from referee Paul McLaughlin after lashing out needlessly at Peter Higgins.
The visitors were behind for just five minutes of the second half as slack marking on the Dundalk right allowed Paul Carey to get his cross away and Phelan was in the right spot at the back post to head the ball home.
The tie was turned on its head 10 minutes later. Waterford left-back Dylan Mernagh delivered a cross over the head of Chris Shields and Ben Ryan, just seconds after coming on as a substitute, guided a fantastic header across Cherrie to put United in the driving seat.
Dundalk's 10 men refused to buckle, however, and half-time substitute McDonnell restored parity with a 25-yard drive that flew past Packie Holden.
Waterford went close to taking the lead again in the 80th minute but Cherrie again stood firm to deny Gary Dempsey and Maguire almost won it at the death for the Blues but his effort went inches wide.
DUNDALK -- Cherrie; O'Brien, Shields, Burns (Whelan 13), Osborne; Shannon, Maher, Mountney, Reilly (McDonnell h-t); Griffin, Rafter (Murphy 85)
WATERFORD UNITED -- Holden; Carey, Breen, Burns, Mernagh; Higgins (Ryan 60), Dempsey, White, Phelan; Keegan (Walsh h-t), Maguire.
REF -- P McLaughlin (Monaghan).