Stuart Lancaster praises his youngsters but admits luck over try

England's head coach, Stuart Lancaster, praised the maturity of his young team after a match described as "brutal" by his assistant Andy Farrell as they remained on course for a first Six Nations Championship Grand Slam since 2003. But Lancaster also admitted his side had been lucky to be awarded their solitary and crucial try by Manu Tuilagi in the second half.

Leicester centre Tuilagi, making his first start in this Championship after returning from injury as a substitute in the 12-6 win away to Ireland a fortnight ago, ran in his 10th try in 19 England Tests with a ball that ricocheted to him off a team-mate in an accidentally offside position. Mako Vunipola's unwitting offence at a time when England were only 12-10 ahead was missed by the referee, Craig Joubert, who was in charge when France – currently winless after three Five/Six Nations matches for the first time since 1982 – lost the 2011 World Cup final to New Zealand.

Asked if his team were lucky with the try Lancaster said: "Possibly on that point, but to an extent in rugby you make your luck in terms of the intensity you go in with at the breakdown and the way you defend. I think if you work hard enough for long enough you get your rewards, and on balance as the game went on we grew stronger, we knocked them back and kept knocking them back."

Tuilagi made a number of typical heavy-hitting breaks and England's captain, Chris Robshaw, said: "Manu was great today, you could really see his power and physicality. Also his ability to hit a great line as well and use his hands. He wanted prove a point and he did that, he was exceptional."

Farrell's son, the England fly-half Owen came off with a quad strain, leaving Toby Flood to kick the two penalties that finished off the French. "It's a massive win for us, " said Farrell Snr, the England backs coach, "simply to come through a brutal game like that, when set-pieces are taking balls off each other and the breakdown is relentless with slow ball coming off it."

With Wales victorious in Italy yesterday, the Six Nations moved closer to a title showdown between England and the Welsh in Cardiff in three weeks' time. Wales have two wins out of three and face Scotland away next, while the Scots and Ireland, with one win in two each, meet in Edinburgh today.

England's penultimate match is at home to Italy a fortnight today, and scrum-half Danny Care – one of a raft of substitutes who helped see off the tiring French – said: "It's all about Italy now, we can't think ahead to Wales. We had one lapse of concentration for Wesley Fofana's try; the rest of the time we limited the French really well. There is going to be an expectation on us to win the tournament. Everybody will expect us to beat Italy. We have to be ruthless and do the job." Tuilagi was "awesome to have in your side", Care added. "The first time he got the ball, he burst through a gap. Every time he got the ball he was exciting."

Lancaster said: "We showed a great level of maturity for a young side with an average age of 24, and with 200-odd caps against a team of 500 caps. We had a tough time in the scrum and I thought the French were excellent at the breakdown. The overall message at half-time was about finishing the game off in the last 20 minutes and I thought that's what happened. Chris Robshaw and Tom Wood were everywhere in the last few minutes, they were rocks in the side. Our bench made a difference. And the ability to problem-solve and come out on the right side is a great skill in teams."