McGeechan predicts tight battle
Former British and Irish Lions boss Sir Ian McGeechan has been hugely impressed by the development of Ireland during this Six Nations.
Going into round four, Joe Schmidt's men remain the only undefeated side having overcome France, Italy and Wales.
They will now face Scotland and England looking to secure their first Grand Slam since 2009 and McGeechan believes that they've improved their game.
"I think we all agree that Ireland are the ones in the driving seat for the championship," he said. "They were impressive again, although they didn't get away from Wales, and tactically they've moved on.
"Joe Schmidt has got his forwards paired up across the field and two half-backs that are totally at ease with the way they want to play, and they're accurate."
Ireland's next challenge will be to defeat McGeechan's countrymen, with Scotland heading to the Aviva Stadium this weekend.
The 71-year-old also believes that Gregor Townsend's team are beginning to find their form after superbly dispatching of England in round three.
He added: "I think it's the two best breakdown teams playing each other head-to-head. It will be quite an interesting battle.
"You've got to give Gregor Townsend a lot of credit. He's forced it through. You can play flat, you don't have to start flat, but it's where you take the ball.
"The Scottish forwards and the speed off the ball against England was also tremendous. There were very rarely any single runners going into contact, there was the ball-carrier and then their support player."
Ireland are 1/6 to beat Scotland and 1/1 to complete a Grand Slam.
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