Richardson had coached Raducanu in her younger days at Bromley Tennis Centre in south London and accompanied the 18-year-old for her campaign at Flushing Meadows.
The experience proved unforgettable as the Briton, ranked No.150 in the world at the time and having played in just one other Major previously – Wimbledon in July – took the title after moving through qualifying and the main draw without dropping a set.
She became the youngest grand slam finalist since Maria Sharapova won Wimbledon as a 17-year-old in 2004 and is the only qualifier in tennis history to win a Major final, male or female.
Her astonishing triumph catapulted her to No.22 in the WTA rankings and Raducanu is now looking for someone to guide her through the next phase of her career.
Speaking at a homecoming event organised by the Lawn Tennis Association, she said: "Where I was at after Wimbledon, I was ranked around 200 in the world and at the time I thought Andrew would be a great coach to trial, so we went to the [United] States but never did I even dream of winning the US Open and having the run I did, and now I'm ranked 22 in the world, which is pretty crazy to me.
"I feel like at this stage in my career, and playing the top players in the world, I realised I really need someone right now that has had that WTA Tour experience at the high levels, which means that I'm looking for someone who has been at that level and knows what it takes.
"And especially right now because I'm so new to it, I really need someone to guide me who has already been through that.
"Obviously having such an experience with your team, it's tough to have that conversation with anyone, but I think for me, it's just really what I need."
It has been suggested Raducanu could look to partner with Darren Cahill, the renowned Australian coach who split with Simona Halep this month.
For now, she is considering when to make a competitive return to action, with the notable Indian Wells Open tournament coming up.
"I'll decide in the next few days where I'm going to go to but, wherever I play next, I'm going to make sure I'm ready. I don't want to jump into things too early," she said.