Hull's longest serving player Paul McShane could have played his last game for the club after manager Steve Bruce hinted at a behind-the-scenes bust-up.
McShane is the only member of the current Tigers squad to have been around in their first Premier League campaign in 2008/09, making exactly 100 first-team appearances.
Only six of those have come this season and the 28-year-old defender has not featured since the 1-0 defeat at Burnley on November 8.
The Republic of Ireland international's Twitter feed last week suggested all was not well when he retweeted a succession of fan messages pleading for him not to be sold or to return to the team.
McShane then posted on Friday night that he would be training with the Under-21s while Hull took on Swansea the following day.
Hull lost the game 1-0, extending their winless run to 10 matches, and Bruce's response when asked about McShane was short on detail but heavy on subtext.
"I could go to Twitter and tell you the reason why he's with the Under-21s but maybe Paul can enlighten you," he said.
"I'll never go to the media or to Twitter on things which remain in-house. But maybe he'll go on Twitter and tell the real reason why, then you'll all know."
Bruce has already called time on loanee Hatem Ben Arfa's brief Hull career after nine unsuccessful loan appearances, and McShane can now expect to join the Frenchman out of the door in January.
The timing is far from ideal, with Michael Dawson out for a month and both Curtis Davies and Alex Bruce coming off with calf complaints on Saturday.
Former Sheffield United defender Harry Maguire was handed a Premier League debut off the bench and could now be thrust into the midst of the relegation battlers' festive fixtures.
James Chester is the only one of Hull's senior centre-halves fully fit at present but he is hoping club captain Davies can make a swift recovery.
"It's an old injury that if he gets a knock on it it's a bit sore but hopefully he'll be okay for the game on St Stephen's Day because we've got a few injuries at the moment," he said. "I think Curtis is all right."
Swansea's unlikely - and unwitting - matchwinner at the KC Stadium was South Korean midfielder Ki Sung-yueng.
He inadvertently deflected the winning goal past Allan McGregor while trying to avoid Jonjo Shelvey's long-range effort.
He will join the club's most frequent scorer Wilfried Bony in leaving on international duty in January, Ki contesting the Asian Cup while his Ivorian team-mate takes on the African Nations Cup.
"Next month, he and I will be away, and Bony is a big player. We need to be ready for when he is away," said Ki.
"I don't think it matters as much about me being away, but Bony is a massive threat every game.
"He is a big player for our team. Apart from the goals he scores, he holds the ball up and passes it. We need him in the team.
"It's disappointing for me that I have to be away for a month from this team but I also want to win the Asian Cup."