"Cahill is an interesting one. He hasn't got in the team at all. He's played in Europa League and the League Cup as well," he told the Transfer Talk podcast.
"He's over 30 years old, obviously it looks like he's not in Sarri's plans. Sarri hasn't really spoken much about Cahill, about saying 'yes I want him to stay' and Fulham, we're told, are interested.
"It could be a good match that one given Fulham's defensive problems.
"An experienced head like Gary Cahill going to Craven Cottage, it could be the difference between Fulham in the Premier League and out of the Championship."
Fabregas and Cahill are tipped to move on from Chelsea in January (Image: GETTY )
Cahill looks set to leave in January (Image: GETTY )
Chelsea: Cesc Fabregas says he'd 'love' to stay at the club
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Sheth believes Fabregas, who has started just one Premier League game all season, could follow him.
"Fabregas isn't getting in the team, they've got a lot of midfielders in that area at the moment, and three or four are getting picked ahead of him," he added.
"Whether Fabregas would want to spend the rest of the season on the bench, I don't know. Fabregas is a possibility [to leave] even though Sarri does want him to stay."
But Sheth can't see Luiz, the defensive rock at the heart of Chelsea's back four, leaving.
David Luiz has played for Chelsea since 2011 but spent two years away at PSG (Image: GETTY )
He continued: "With regard to who they would potentially release in January, I can't see a situation where they'd allow David Luiz to go.
"Sarri has been picking him every single week and I just can't see how they would release someone like David Luiz.
"As far as Luiz is concerned, he's hopeful the club can reach an agreement to stay beyond this season but again that policy of only offering one-year contracts to players over 30 could prove to be a sticking point.
Fabregas has won two Premier League's with Chelsea (Image: GETTY )
"He was asked to which he would accept a one-year extension - 'we're still talking, let's see, let's see what the future brings, I love this club, everyone knows that I want to stay'.
"Sarri has already said aside of Luiz, he wants Fabregas to stay but he admits this will be very, very difficult to keep both of them at the club.
"Luiz, I would say if I was to put money on now which I'm not, I would say he would stay."