Pontypridd's first game ended in a Roman holiday for the Sardis Road men as they walloped Rugby Roma 60-18.
Two second half tries by super sub Sonny Parker sealed a comfortable win for Pontypridd at the Italian national ground Stadio Flaminio.
The New Zealand-born centre's opener was a real peach as he ripped through the Roma defence from 55 metres to give his side a 20-point cushion.
Neil Jenkins showed he has lost none of his kicking prowess smacking seven out of eight conversions and landing two penalties for a 25-point haul.
Saracens Welsh international centre Tom Shanklin went on a Romanian rampage as he mercilesly exposed a fragile Dynamo Bucuresti defence.
Shanklin romped over for five tries as Saracens cantered to an 87-11 win in an East European citadel which fell so easily to the Londoners.
Novice winger Chris Hall came to Leeds' rescue with a second-half try hat-trick to snatch a 29-23 win at Petrarca Padova.
The home side led 17-10 at half-time and the boot of winger Sebastian Francesio kept them in touch throughout an exciting second 40 minutes.
French aces Colomiers were posed few problems at Italian side L'Aquila as they turned on the style in the second half.
They were held to 0-15 at the interval but opened up afterwards to run out 58-14 winners.
Winger Vincent Noutary, centre Michael Mabilon and No 8 Romain Rysman were the French stars grabbing two tries apiece.
Harlequins took Welsh also rans Caerphilly to the cleaners at Virginia Park crushing them 73-20.
Harlequins ran in 11 tries with two apiece for wingers Matt Moore and Rob Jewell and scrum half Nick Duncombe.
Winger Geraint Lewis and centre Ryan Howells crossed for consolation tries for a totally outgunned Caerphilly.
Rugby Treviso shocked Castres Olympique 22-9 with Irishman Simon Mason their hero cracking five penalties and adding the conversion to Francesco Mazzariol's try.
John Rudd put London Wasps on course for a second round clash with French side Bordeaux-Begles in the Parker Pen Challenge Cup with a hat-trick of tries in the first-leg of their game against Rugby Parma.
The Italians proved to be tougher opponents than expected and trailed 26-10 at half time. By that time the 21-year-old Rudd had only managed one try, but after the break he completed his hat-trick to steer Wasps to a 40-24 victory.
Outside half Mark van Gisbergen was the other star for the Wasps as he helped himself to 19 points with the opening try of the game and 14 points with the boot.
But while coach Warren Gatland will have been pleased to see his side pick up an away win, and avoid a repeat of the defeat Wasps suffered on their last European venture to Italy, he won't have been happy to see his side concede three tries.
Wing Alensa Tuilagi, brother of Leicester's Freddie, grabbed a first-half score for Parma and they picked up two more in the final quarter to give the 1,500 strong crowd something to shout about.
Bordeaux were forced to work hard for their 37-31 first-leg victory in Madrid against the Spanish league champions, La Moraleja Alcobendas, outscoring them by five tries to three.
That will make them favourties to go through to the next round, although they will have to be wary of the boot of Czech international Martin Kafka in the return game. Kafka helped himself to 16 points with two conversions, three penalties and a drop goal.
Irish referee Simon McDowell had to be escorted from the field as Newcastle pulled over a valuable seven-point first-leg win over Grenoble, 19-12.
The home fans were angered by several of McDowell's decisions, but ill-discipline from their players had more to do with the scoreline.
In the end, England outside half Jonny Wilkinson was able to punish the home side even more with four penalties and a conversion of Martin Hurter's push over try.
All the points for the Falcons came in a wind-assisted first-half, while Grenoble could only manage a try by scrum-half Yohann Authier. Both Hurter and Jean-Francois Martin-Culet spent 10 minutes in the sin-bin in the first-half and things got even worse for the home side when prop Martial Bigou was stretchered off.
The only score in a tight second half came from home centre Nicolas Carmona, but the Falcons held on for a good win. Victory in the second leg at Kingston Park this weekend should see them through to face either Rugby Treviso or Castres Olympique in round two.
One French side that did win on home soil was Pau, who edged out Bridgend 18-6 in a tight game.
Bridgend had the majority of possession and territory, but couldn't press home their advantage.
In wet conditions they made mistake after mistake to let Pau off the hook, with fly-half Craig Warlow missing four penalty goal chances.
The only try of the half came after David Arrieta launched a counter-attack and French star Damien Traille did the damage with a superb run from his own 22 to set up flanker Pierre Som for the score.
And with David Aucagne adding penalty goals in the fourth and 19th minutes, Bridgend were left rueing those missed chances.
They clawed back to 6-11 on the back of two Warlow penalty goals early in the second half, but Pau had the final say with a try to centre Eric Artiguste.
Connacht got back to winning ways, after losing their unbeaten record this season to Pontypridd in the Celtic League last weekend, with a 26-12 victory at Mont-de-Marsan.
Eric Elwood matched Fijian favourite Waisale Serevi with four penalties, but the former Irish outside half also converted both of his sides tries from Wayne Munn and Eoin Reddan.