UPDATE 1-Rugby-Mighty scrum shoves England to Ireland victory

* Immense forward display earns 30-9 win

* England finish second behind Wales (Adds details)

By Mitch Phillips

LONDON, March 17 (Reuters) - England's rebuilt side completed a satisfying Six Nations championship when, on the back of a devastating scrum, they beat Ireland 30-9 on Saturday to finish second behind grand slam winners Wales.

Six penalties by nerveless flyhalf Owen Farrell, a penalty try and a score for scrumhalf Ben Youngs were a fair reward for England's dominance, particularly in the second half when they took Ireland to the cleaners in the scrum.

England, the defending champions, finished second on eight points after earlier away wins over Scotland, Italy and France to leave interim coach Stuart Lancaster in a strong position to be given the job of replacing Martin Johnson on a permanent basis.

Having entered the championship with a new coach, new captain, a host of new players and with their reputation in tatters after the World Cup, it has been a remarkable turnaround under the uplifting guidance of Lancaster.

Ireland, who had won seven of their previous eight championship meetings with England, finished third on five points, ahead of France on points difference.

Wales's grand slam-clinching victory over France in Cardiff earlier on Saturday meant that England could not retain their title but, following on from their excellent win in Paris last week, they had plenty to play for against a team who have given them so much trouble in recent years.

A slippery ball and a succession of handling errors made for an open first half with both sides seeing glimpses of opportunity but generally unable to string together enough passes to take advantage of them.

There were turnovers aplenty as players struggled to cling on to the ball in contact and both sides generally opted for the least-risky kicking option when things got tight.

England edged the half on the scoreboard with three Farrell penalties, the third coming after their impressive pack had taken a second successive scrum against the head, to two from Jonathan Sexton.

The first try looked a certainty six minutes into the second half when Tom Croft broke through but dropped the ball in the act of passing to the unmarked Ben Foden with the line at his mercy.

England had points on the board soon after though when they demolished the Irish scrum on the 22 and earned another successful Farrell penalty and that set the tone for the remainder of the match.

Sexton did land another penalty but it was a rare foray by an Irish team who, a year ago, took the gloss off England's title celebrations by thrashing them in Dublin in the final game.

After 57 minutes another powerful England scrum drove forward and man of the match number eight Ben Morgan touched the ball down but the referee had blown for an England penalty a second before.

The home dominance was then underlined when, after another collapse, Welsh ref Nigel Owens ran out of patience and awarded a penalty try.

The home crowd, so long starved of what used to be their staple diet, roared their approval of the meaty fare as England opted for scrum after scrum and, on every occasion left a pile of green shirts spread around the turf.

Another scrum penalty opened the way for Youngs to take a tap and scuttle through for the icing on the cake and make it a St Patrick's Day to forget for the visitors.

"I'm really pleased with the performance in difficult conditions. "We were outstanding in every department," Lancaster told the BBC.

"At the outset there was a long-term plan, it was around giving some young players some experience. but they showed great belief."

Asked if he thought he had done enough to earn the job full time Lancaster said: "That's for others to decide.

"But if you'd said to me a few years ago I'd be walking around Twickenham applauding 82,000 people after this I'd have taken it." (Editing by Justin Palmer)