Sunderland are currently sat in 23rd place in the Championship table.
Coleman initially sparked an improvement in Sunderland’s form, but the Black Cats have reverted to type more recently.
Sunderland have won just once in their last six outings, and were beaten 2-0 by Ipswich Town in their most recent fixture.
If Coleman ever had any doubts over how tough it would be to save Sunderland, he will now have realised the scale of the problems at the Stadium of Light.
And Phillips fears that his former club could be set to face back to back relegations and drop into League One.
“I think they could go again this season. It would be an absolute disaster,” Phillips said.
“Chris may be sitting in a room having some regrets about taking over. I’m fed up with answering questions about what’s gone wrong – I just don’t know. Until the chairman sells the club and the right people can come in and get rid of a lot of players, unfortunately they could be plying their trade in League One next year.”
Sunderland are currently in 23rd place in the Championship table, and are battling against being cut adrift.
The Black Cats just cannot string together a run of positive results, with frustrations rising on Wearside.
Sunderland are next in action at the weekend, when they take on Bristol City at Ashton Gate.
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