Having first met Andy Farrell when he was 12, George Ford knows better than most the calibre of the man who on Sunday will attempt to lead Ireland to a Triple Crown at Twickenham in his first season as a head coach.
Ford was in year eight at St George's School in Harpenden when the Farrell family moved in 10 minutes down the road, the Wigan star having signed for Saracens, where George's father, Mike, was head coach.
Later, after he and Owen Farrell had operated in tandem at age-group level for England, including at the 2011 Junior World Championship, when they reached the final, Ford was coached by Farrell when the former rugby league Man of Steel was defence coach at England under Stuart Lancaster.
So the England fly-half knows exactly what he is talking about when he says Ireland will be "hugely motivated" to win on Sunday, particularly given the 57-15 drubbing they received when they were last at Twickenham, for a World Cup warm-up match last summer.
"I'd think every head coach coming here playing England would be motivated to come and win," said Ford. "But what I know is he (Andy) is like Owen, they're very competitive guys and he will be doing his utmost, Andy and the rest of the Irish squad, to come and get a win.
"I'm not sure (whether they will use the defeat last summer as motivation). I'm not in their camp. What I'd say is it's a completely different game, different circumstances. I'd imagine it would be a bit closer and a bit more of a contest and a tough Test match."
Ireland have seen off Scotland and Wales in impressive fashion in the opening two rounds and look to be enjoying themselves again after the intense approach of previous head coach Joe Schmidt. Ford said their new-found positivity had not gone unnoticed.
"They are probably trying to develop their attack in terms of phase-play stuff," he said. "They have got (new attack coach) Mike Catt there as well, who is obviously a very good coach. I have experienced that with Catty being here. He thinks about the game from a very attacking point of view.
"We are glad to be back at Twickenham and we will be putting all our energy into preparing as well as we can because we will need to be somewhere near our best."
© Daily Telegraph, London