Bridgend led the way with their one point victory over Bath at home on the same night as Llanelli took a bite put of Sale Sharks in Manchester.
Theri lead was followed by Newport, who beat London Irish iin the Heineken Cup and then Pontypridd, who put Leeds Tykes to the sword at Sardis Road.
The only English victory came at Northampton, where the Saints beat Cardiff 25-11in the Heineken Cup to end the blue and blacks hopes of reaching the knock-out phase.
"Leeds certainly found out what it takes to travel to a place like Sardis Road. It really is a case of preparing to go to war," said Lewis.
"Their director of rugby Phil Davies threw in a few young forwards, but they weren't up to it mentally. As a result they were blown away.
"The win by Llanelli at Sale proves that the best teams in Wales are very much on a par with the top sides in England. We beat Bath by a point, but we know we are going to have to improve in next weekend's return leg.
"Welsh teams are always difficult to beat at home, especially against English teams,, because the pride comes shining through. You only had to look at the way Newport got stuck into London Irish and Ponty tore into Leeds to see that.
"But we will all have to improve when we travel away at the weekend. The English teams will no doubt be looking for revenge and we'll have to raise our level of performance by 30 or 40%."
Having seen Bridgend and Llanelli lead the way, Newport upset the odds to post their biggest win of the season with a 16-12 home defeat of London Irish. That was their first win in three outings in Pool 5 of the Heineken Cup.
It took some great defence, and a try from a close range line-out drive from man of the match Jason Forster, to give Newport only their third win in 11 starts this season. Barry Everitt kicked four penalties for the Irish, but his skipper Ryan Strudwick shunned to simple shots at goal in the second half as he opted to go for a try.
That didn't please his director of rugby, Conor O'Shea, who had to reflect on a defeat in a game that his side dominated both territorially and in terms of possession.
"We've got something to build on for the rest fo the season after this result. It's given us a huge shot in the arm in terms of confidence," said Newport coach Leigh Jones.
"It looks as though Toulouse are favourites to win our Pool after their third successvie victory, but we won't be going to London Irish merely to make up the numbers.
"We will go to Reading full of confidence and after this I don't think it's beyonjd us to go to Toulouse and win."
Cardiff coach Dai Young fell foul of the referee again as he went to the sin-bin for the second successive weekend as Cardiff collapsed a week after their Celtic League quarter-final victory at Edinburgh.
While he left the field with Scottish international Martin Leslie the previous weekend, this time he went on his own for interfering with a quick tap penalty. While he was on the sideline Northampton conjured up a try for England wing Ben Cohen, which Paul Grayson converted, and the visitors were 25-11
ahead and never likely to be caught.
Young felt hard done by at the end of the game, claiming Scottish referee Iain Ramage had given him the go-ahead to tackle Cohen.
"They took the tap and Ben ran straight at me. The referee told me to let him go and I did," said Young.
"The ref than said the advanatage was over and I tackled him. I did feel hard done by."
Pontypridd's new Welsh star Sonny Parker scored two and made another try in front of Welsh coach Steve Hansen as the 'Valley Commandoes' beat Leeds 37-23 at Sardis Road in the first leg of their second round PARKER PEN CHALLENGE CUP tie.
A GOOD NIGHT FOR WALES
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