(CNN) -- Holders Manchester United swept into the last eight of the Champions League with a 2-0 second leg victory over Jose Mourinho's Inter Milan -- and Arsenal joined them after a dramatic penalty shoot-out win at Roma.
Ronaldo heads his first European goal since the Champions final win last May to put United in the last eight.
That means all four Premier League contenders are in the quarterfinal draw on March 20 after Liverpool and Chelsea triumphed on Tuesday.
United manager Alex Ferguson had only beaten a Mourinho-led team once in 13 meetings before Wednesday's clash, but Cristiano Ronaldo's first European goal since the final triumph last May, three minutes after halftime, saw off the Inter threat.
Nemanja Vidic had given quintuple-chasing United a dream start when he powered home his sixth goal of the season after just three minutes.
Arsenal went to the Stadio Olimpico -- the venue stages this year's final -- with a 1-0 first leg advantage that lasted just 10 minutes of the return when Brazilian defender Juan capitalised on some poor defending to fire the Italians in front.
The Gunners grew in stature as the match went on, but could not find a way through as extra-time passed -- missing several good chances in the process.
Roma's Max Tonetto missed his crucial sudden-death spot-kick as Arsenal won 7-6 after Eduardo saw his opening effort saved by Doni.
Fortunately for Arsenal Mirko Vucinic stabbed his attempt straight at Almunia three kicks later.
Walcott, Baptista, Nasri and Denilson all scored for Arsenal, before Totti stepped up to send the shoot-out into sudden death at 4-4.
Toure coolly dispatched his effort, as did Sagna and then John Arne Riise for Roma. With the tally at 6-6, Diaby slotted home before the pressure got to Tonetto as he blazed the ball over.
United's early goal at Old Trafford came when Ryan Giggs aimed an inswinging corner to the far post and Vidic climbed unmarked to direct a header beyond keeper Julio Cesar and into the bottom left-hand corner from eight yards.
United needed another goal to counter the threat of an Inter away strike after the goalless first leg in the San Siro, but instead it was Serie A leaders who stepped up the pace.
They cam desperately close to an equaliser following a free kick in the 28th minute when Sweden striker Zlatan Ibrahimovic nodded the ball into the turf from six yards and saw it bounce up and onto the bar.
Inter suddenly had United on the backfoot and after 36 minutes Dejan Stankovic fired a low 25-yard drive just past the right-hand post.
John O'Shea squandered a great chanced for United when he sidefooted a Rooney pass into the body of Julio Cesar.
Inter should have made United pay when Stankovic fired wide after stealing round the back of the United defense onto a curling pass from Ibrahimovic.
Alex Ferguson's half-time rocket certainly did the trick with United claiming that all-important second goal within three minutes of the restart after Giigs and Wayney Rooney combined on th edge of the area.
Rooney, faced with two defenders in front of him, lifted a cross towards the six-yard box where Ronaldo rose to head home his 16th goal of the season.
Cambiasso tested Van der Sar with a raking 25-yard drive in reply before substitute Adriano's shot on the volley beat Van der Sar, only to strike the goalkeeper's right-hand post.