Darius Kierans’ side looked to be staring defeat in the face when they firstly lost midfielder Stephen Maher to a needless red card before seeing their lead, which came courtesy of Lorcan Shannon, cancelled out by early second-half headers from Paul Phelan and Ben Ryan.
However, a 25-yard thunderbolt from local man McDonnell rescued what could prove to be an invaluable draw for them ahead of Friday night’s second leg in the RSC.
While the game is still evenly poised ahead of the trip to the South East, there will be little doubt over which side was more happier with last night’s result.
Waterford were already on top when they fell behind in the 22nd minute. A superb pass from Maher released Chris Reilly down the left with his first-time cross picking out the inrushing Shannon, who made no mistake from close range.
The game swung dramatically back in the Blues’ favour on 33 minutes though when Maher needlessly kicked out at Peter Higgins after a challenge along the touchline, leaving referee Paul McLaughlin with no option but to produce the red card.
Buoyed by the man advantage, Waterford needed less than five minutes to level after the restart. A quick throw by Paul Carey was hooked across goal by Sean Maguire with Paul Phelan’s downward header creeping under Cherrie’s body.
The Blues then hit the front on the hour mark when Dylan Mernagh’s cross from the left wasn’t dealt with by the Dundalk defence, allowing substitute Ryan to head home with his first touch.
At that point there looked like being only one winner. That was until McDonnell sent a thunderbolt past Packie Holden in the 76th minute with his side just managing to hold out for the draw.
DUNDALK: Cherrie; O’Brien, Burns (Whelan 13), Shields, Osborne; Shannon, Mountney, Maher, Reilly (McDonnell ht); Rafter (Murphy 85), Griffin.
WATERFORD UTD: Holden; Carey, Breene, Burns, Mernagh; Phelan, White, Dempsey, Higgins (Ryan 60); Maguire, Keegan (Walsh ht).
Referee: P McLaughlin (Monaghan).