The frontman left St. James’ Park to join Liverpool in January 2011 but put pen to paper on an initial one-year deal with the Magpies on Thursday.
Born and raised in Gateshead, Carroll came through United’s academy setup before making his first-team debut as a 17-year-old, against Italian side Palermo, in 2006.
He played a fundamental role as the Magpies returned to the Premier League at the first time of asking in 2010, and struck 11 times in 19 appearances back in the top flight before making a £35M move to Anfield.
“That was a bit of a whirlwind, as well,” Carroll said. “That happened on deadline day, as we know. It was a quick turnaround and that’s how it went. I enjoyed the time I spent here and hopefully I can carry on where I left off.
“When I left eight and a half years ago I was scoring goals, I was enjoying my football. It’s been a pretty tough time since then and I just want to get back to that.”
Carroll was restricted to 12 Premier League appearances for previous club West Ham United last season – all bar two coming from the bench – but insisted he is firmly on the right track in his bid to return to full fitness.
“The last couple of years, it’s been really tough. I’ve had a single injury that’s just been niggling away and I’m hoping to get over that,” he said. “I’m feeling good now, I’m outside running, and I want to get a clear mind, a fresh start and what better place to be than here?
“I’ve been working really hard. I’ve still been in every day over the summer; there’s been no holiday or anything. I’ve been in at West Ham, training every day with the physios and still being about with the lads. I’ve been working hard, sticking to schedules and now I’m here.”