The Republic's record goalscorer and skipper of both club and country at present bagged goals number 30 and 31 as Steve Staunton's side hammered the Danes 4-0 in Copenhagen.
Robbie chipped home from Andy Reid's pass after 29 minutes and added a somewhat fortunate second two minutes later when keeper Jesper Christiansen punched the ball against him and it flew into the net. Reading's Shane Long scored twice after the break to complete the rout.
TEEMU ON TARGET
Robbie might have netted twice but team-mate Teemu Tainio arguably scored the most important goal of the night as Finland beat Kazakhstan 2-1 in European Championship qualifying.
The midfielder, back from illness, struck the winner and it could be a key goal in Group A - Finland began the day level on 14 points with Portugal and Serbia and five adrift of leaders Poland, but Portugal were held 1-1 in Armenia and Serbia lost 3-2 in Belgium, so Finland's success gave them control of second place.
As expected, Gareth Bale played the first 45 minutes for Wales as John Toshack's team completed a fine 1-0 friendly win against Bulgaria. It was Gareth's first action since suffering knee and thigh injuries in our friendly at St Patrick's on July 12.
Meanwhile, Paul Robinson played the first half as England suffered a 2-1 defeat against Germany at Wembley. Jermain Defoe was an unused substitute.
Robbie Keane broke through the 30-goal barrier as the Republic of Ireland stunned Denmark in Wednesday night's international action.