Chelsea centre-back Gary Cahill could be on his way out of Stamford Bridge in January after falling down the pecking order under Maurizio Sarri.
The former England international was a first-team regular last season under Antonio Conte but has played just 21 minutes of Premier League football this term.
Galatasaray have been closely linked with the 32-year-old in recent weeks as they look to bolster their defensive options.
However, they are likely to face competition from West Ham United. According to the Mirror, the hammers are weighing up a move for Cahill in January.
Per the source, West Ham boss Manuel Pellegrini has the support of the board and will be able to reinforce his squad in the winter transfer market.
Cahill has played just three games for Chelsea this season and has started in the Europa League and League Cup.
Galatasaray are on the hunt for a new defender after failing to replace Jason Denayer over the summer. Denayer returned to City after his loan expired and subsequently joined Ligue 1 giants Lyon.
Chelsea are back in action this weekend when they host Manchester United at Stamford Bridge on Saturday. Galatasaray meanwhile take on Bursaspor in the Turkish Super Lig on Friday.