Ireland coach Joe Schmidt says the fact his side had more experience in their ranks proved crucial in their Six Nations win over England in Dublin.
The 19-9 victory kept the Irish on course for a possible Grand Slam.
"We had core leaders and had a bit more experience out there than England. They had a few missing," Schmidt said.
Jonathan Sexton was forced off by a hamstring twinge and Sean O'Brien was concussed but Schmidt said it was unclear how serious the knocks are.
O'Brien, who has just returned after missing much of the last 18 months with a shoulder injury, was replaced after he stumbled badly when trying to get up from a heavy hit in the first half.
Sexton left the field holding his hamstring after kicking Ireland's final points midway through the second half and would be a major loss if he was unfit to face Wales in two weeks time.
"Johnny just felt a twinge in his hamstring when he was kicking that conversion from the corner, we haven't had that assessed so I can't really comment as to the severity or non severity of that," added Schmidt
"Sean O'Brien, we're not quite sure how it happened, he's going to go through the protocols in the next six days.
"He's certainly asymptomatic at the moment, he's fine, just a little bit grumpy and disappointed he didn't get to see out the match."
Centre Jared Payne went off late in the match after taking a bang to the head but Schmidt that he had not suffered concussion.
Schmidt added:"We rely on Jonny Sexton and Conor Murray a lot - they move us about the pitch in the right manner and it's hard to quantify what they add to the team."
The Kiwi-born coach added that it was particularly pleasing to win against the team who were the only other unbeaten side in this year's championship.
"England have set the benchmark, particularly in their opening game against Wales, and we knew that despite having a six-point half-time lead, they were going to come back at us," the New Zealander said.
"But we managed to dig deep and keep them off our line. I have a great bunch of players and I'm learning as much from them as they are hopefully learning from me."
|Ireland's 2015 Six Nations matches|
|7 February||Italy 3-26 Ireland|
|14 February||Ireland 18-11 France|
|1 March||Ireland 19-9 England|
|14 March||Wales (a)|
|21 March||Scotland (a)|
The success at the Aviva Stadium made it 10 consecutive wins for Ireland, equalling their best-ever sequence of results.
"Joe is an intelligent guy - he's an excellent coach, plus we have a very good provincial set-up, a lot of strength in depth and genuine competition for places," Ireland captain Paul O'Connell said.
"We have a lot of respect for this England team, so to beat them we are really delighted.
"Our discipline was good in the first half and our first 20 minutes of the second half was excellent. We played some good rugby."
He added Sexton, who scored four penalties and a conversion, had "kicked really well", while Robbie Henshaw had scored " a great try".
"That helped give us a 16-point lead and some massive breathing space - the only disappointment was that we sat back a bit after that," he said.
"Wales put themselves in with a good chance by beating France, so it's going to be incredibly difficult in Cardiff."