The BBC unceremoniously dumped Tom last year in favour of Boy George, leaving Will as the only star involved in every series of the show.
But the 'It's Not Unusual' singer is now back on the talent contest as it heads to ITV for its sixth run - and Will says Tom's return is the reason he moved with it.
The Black Eyed Peas frontman told the Daily Mail: "I wasn't going to come back if Tom wasn't part of it.
"I think it needs Tom Jones, his experience. It gives the show credibility."
Will isn't the only coach in awe of Tom.
Bush rocker Gavin Rossdale, a new addition to the show, added: "Everyone defers to Tom. He's a king. I feel like he's our Elvis."
This year's panel is completed by Oscar-winning Dreamgirls star and former American Idol contestant Jennifer Hudson.
Tom recently took a swipe at BBC bosses over his sudden ousting.
"When ITV asked me back, it was nice to know they felt what happened to me shouldn’t have," he commented.
The Voice's big ITV relaunch begins on Saturday 7th January at 8.00pm, with the Blind Auditions getting a new twist.
Coaches who do not press their button to turn for an artist will now not get to meet them.