Paris - English clubs completed a clean sweep of four teams into the Champions League quarter-finals following a cliffhanger shootout victory by Arsenal against Roma on Wednesday night.Defending champions Manchester United had already beaten Inter Milan, and on Tuesday Liverpool and Chelsea had booked their passage. When Max Tonetto shot high over the bar it gave Arsenal passage into the last eight 7-6 on penalties after the match ended 1-0, 1-1 on aggregate, after extra time."We needed to show our nerve tonight and determination," Arsenal manager Arsene Wenger told Sky Sports. "We were a bit nervous at the start and gave a goal away more by nerves than them creating the chance."I must pay tribute to the nerves of my team. There is something in there that comes out, that is huge mental strength."Our character has been questioned many times. I've said many times that this team is very strong."At Old Trafford headers by Nemanja Vidic, who outfoxed Patrick Vieira in the box, and then Cristiano Ronaldo put United through 2-0 at the expense of Jose Mourinho's Inter Milan, who never really got on equal terms with their opponents.Barcelona's Thierry Henry scored his 49th and 50th goals in the competition, putting him fourth in the all time list, as Barcelona beat French champions Lyon 5-2 at the Nou Camp stadium.Porto and Atletico finished goalless in Lisbon but the 2-2 draw in the first leg in Spain meant Porto went through on away goals. The eight teams which go into the Friday March 20 draw are Liverpool, Manchester United, Arsenal, Chelsea, Bayern Munich, Villarreal, Porto and Barcelona, with no Italian team for the first time in seven years. "It was one of those long European nights where you don't know if you're watching a game of football or watching a game of suicide," United manager Alex Ferguson said afterwards."After scoring the first goal, I thought we would go on and kill them. But after going ahead we started trying to put icing on the cake and we were lucky to be in front at half-time."Ferguson added: "I thought we could score a few goals but then we started doing flicks and back heels, hitting balls into space where no one was."It was really reckless football and it allowed Inter Milan to get a grip of the game. From the middle of the first half to the end of the first half they were the better team."Despite his frustration, Ferguson took heart from the fact that his side had come through a tough tie."We changed the system at half-time, closed the door on (Esteban) Cambiasso and we were a bit better in the second half," the Scot added."We played a team at its maximum, potential-wise with all the experience they have. And they played to their maximum."To get through that tonight was a big plus for us, because we will be better in the next round. We can play better than that but I am happy to get through it."Inter Milan manager Jose Mourinho claimed United had enjoyed more than their fair share of lucky breaks.But he had no doubt about the English champions' ability to complete an unprecedented quintuple because of the way Alex Ferguson's side have matured over the last two seasons. "They have basically the same team as when I was at Chelsea," Mourinho said. "There is only Berbatov who is new. But they have been together for four or five years. They are not young anymore -- the age average is 26-27 if you forget Giggs and Scholes. "They are in the right moment to be at the top of their careers. They reached the maximum level. They have experience, quality, great physical condition and intensity in their game. That is what the Champions League is about. So yes, I think they can do it (win five trophies)." The five trophies would be English Premiership, FA Cup, League Cup, World Club Cup, and Champions League. Barcelona striker Lionel Messi said: "We weren't afraid, but it's true after those two goals (by Lyon) we were a little surprised, we had a complicated moment."But even so we weren't in a very dangerous situation, we were all united, we wanted the same thing." Lyon president Jean-Michel Aulas said: "We're disappointed that tonight we were outclassed by Barca. But it's also a sign that the top clubs in France are not at the same level as their foreign rivals."