Mullins was also able to empty the bench to full effect with Limerick cruising to victory in Dungarvan.
Limerick began the defence of their Munster U20 Hurling Championship with a 1-18 to 1-14 win over Waterford in their rescheduled round one clash in the Fraher Field on Saturday afternoon.
Newcastle West’s Con Hayes grabbed the decisive goal early in the first half for Limerick who didn’t trail for the remainder of the contest after taking the 1-1 to 0-2 lead.
Senior panelist Patrick Fitzgerald kept Waterford in it with a tally of 1-11, including their last-minute goal that put a gloss on the final result.
But the Deise were too dependent on placed balls with just five scores coming from play whereas Limerick fired 1-13 outside of frees.
Mullins was also able to empty the bench to full effect with Liam Lynch and Liam Dennehy striking over on their introduction with Limerick cruising to victory.
Limerick’s first dominant spell came after Hayes goal as they moved 1-6 to 0-3 clear shortly after, Hayes, Paddy O’Donovan, Barry Duff and John Kirby finding the target.
Fitzgerald had Waterford’s sole response in that time with a free for a Deise side that will rue missed goalscoring chances, although Limerick’s Josh O’Reilly was excellent in preventing the hosts.
Shane O’Brien got off the mark with a solo score in the 20th minute to restore Limerick’s six-point advantage but frees from the Ballygunner native Fitzgerald kept his side in the game, reducing the margin to 0-10 to 1-9 at the half.
Two minutes into the second half, Fitzgerald brought the teams within a point but that was close as the Deise would get with Fintan Fitzgerald and Adam Fitzgerald firing over for Limerick immediately after.
A 65′ from Fitzgerald made it 0-13 to 1-13 with a quarter of an hour to play but the Limerick response came from Adam English and O’Donovan to re-establish the six-point cushion as they held out comfortably from here.
Next up for Diarmuid Mullins and co is Clare this Wednesday in the TUS Gaelic Grounds at 7pm.
Scorers for Limerick: Paddy O’Donovan (0-6, 5frees), Con Hayes (1-2), John Kirby and Adam Fitzgerald (0-2), Adam English, Fintan Fitzgerald, Barry Duff, Liam Dennehy, Shane O’Brien and Liam Lynch (0-1).
LIMERICK: Josh O’Reilly; Ronan Lyons, John Fitzgerald, Evan O’Leary; David Fitzgerald, Cian Scully, Ethan Hurley; Barry Duff, Adam English; Fintan Fitzgerald, Paddy O’Donovan, John Kirby; Con Hayes, Adam Fitzgerald, Shane O’Brien.
Subs Used: Joseph Fitzgerald for Duff (39), Oisin O’Farrell for A Fitzgerald & Liam Lynch for Hayes (46), Liam Dennehy for F Fitzgerald (57), Shane O’Neill for Kirby (60)
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