In August, Welsh singer Tom shared his upset that he had been dropped as a coach on the BBC One talent show after four years of service.
Now speaking on Alan Carr's Chatty Man Christmas special, Emma said she and Marvin "didn't get a chance" to say goodbye to Tom.
"It was sad to know that he wasn't coming back because he's such a nice man and he's just utterly professional and a gentleman and has that cheeky little glint in his eye," said Emma.
Marvin agreed, adding: "And he's still a great singer."
Sir Tom – and fans – were left shocked when bosses dropped him ahead of the brand new fifth series.
Tom, 75, criticised the BBC and producers over the way his axe was handled, saying he was "deeply insulted" to be let go with no "consultation or conversation".
BBC's Director of Television at the time, Danny Cohen, also apologised to Tom in a statement: "I've got huge respect for Tom and I'm truly sorry he's upset, because I am a big fan of his.
"I think he's a gentleman, I think he's an extraordinary figure in music and you'll have seen the huge respect that all of the artists have had for him on The Voice throughout.
"These things happen over time, but I would never would want Tom to be upset and I am sorry that's the case. I'd like him to go out on the BBC this year in something else... I hope he's back on the BBC very soon, I really do."
Alan Carr's Chatty Man Christmas special - 9pm, Channel 4, on Friday 25 December - Christmas Day
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