Wales made a nervy start despite Jones giving them a third-minute lead with a simple penalty from in front of the posts. He missed a more difficult opportunity in the 10th minute but soon made amends by rounding off a glorious Welsh move to claim the game's opening try in the 16th minute. The diminutive fly-half added the extra points to give Wales a 10-0 cushion.
Ireland hit back on the half hour, centre Andrew Trimble cutting through to send No 8 Stephen Ferris over in the left-hand corner for an unconverted try - and 10-5 was how it stayed until the interval.
Whatever coach Chris Davey said must have worked as Wales came out with far more purpose after the break and it took just three minutes for them to extend their advantage, Jones and centre Andrew Bishop combined to put wing Chris Czekaj over in the corner. Jones converted to make it 17-5.
Jones added a penalty in the 50th minute and soon after improved a Bishop try which put the result beyond doubt at 27-5.
Czekaj iced the Welsh cake with his second try two minutes from time.
Wales: Tries - C Czekaj (2), M Jones, A Bishop; cons - Jones (3); pens - Jones (2)
Ireland: Try - S Ferris