The Scarlets turned it on the second half to see off Aironi 32-9 in their RaboDirect PRO 12 season opener on Sunday.
Aironi, who have yet to register an away win in the league since their introduction to the competition last year, made the home side battle all the way, and found themselves on level terms on 46 minutes following a Naas Olivier penalty - his third of the game.
The Scarlets, though, sprung into life and added to Dan Newton's three first half penalties with the first try of the game with half-an-hour left on the clock.
Nigel Davies' side finally put together a sustained period of attack and Ben Morgan's run ended with Josh Turnbull putting prop Rhys Thomas over at the corner.
Newton converted and added two further penalties to open up some daylight between themselves and the visitors.
The Scarlets' second try of the evening came when wing Andrew Fenby peeled away from a ruck to sprint home. Newton again converted.
Rhys Jones, on as a late replacement for Newton, completed the scoring with a penalty right at the death.
Tries: Fenby, RM Thomas
Cons: Newton 2
Pens: Jones, Newton 5
Pens: Olivier 3
Scarlets: 15 Daniel Evans, 14 Lee Williams, 13 Rhodri Gomer-Davies 12 Aled Thomas, 11 Andy Fenby, 10 Dan Newton, 9 Rhodri Williams, 8 Ben Morgan, 7 Josh Turnbull, 6 Rob McCusker, 5 Dominic Day, 4 Aaron Shingler, 3 Rhys Thomas, 2 Emyr Phillips, 1 Iestyn Thomas (c).
Replacements: 16 Kirby Myhill, 17 Phil John, 18 Simon Gardiner, 19 Lou Reed, 20 Richie Pugh, 21 Justin James, 22 Rhys Jones, 23 Adam Warren.
Aironi: 15 Ruggero Trevisan, 14 Riccardo Pavan, 13 Roberto Quartaroli, 12 Gabriel Pizarro, 11 Giovanbattista Venditti, 10 Naas Olivier, 9 Tito Tebaldi, 8 Nick Williams, 7 Nicola Cattini, 6 Josh Sole, 5 George Biagi, 4 Joshua Furno, 3 Luke Redolfini, 2 Roberto Santamaria (c), 1 Matias Aguero.
Replacements: 16 David Giazzon, 17 Alberto De Marchi, 18 Fabio Staibano, 19 Filippo Ferrarini, 20 Frans Viljoen, 21 George Bronzini, 22 Alberto Benettini, 23 Gilberto Pavan
Referee: Andrew McMenemy