Mason suffered a fractured skull after a clash of heads with Cahill during Chelsea’s 2-0 win over Hull City yesterday.
Mason is in a stable condition after being taken to St Mary's hospital in Paddington, London after the incident at Stamford Bridge.
And it is understood Chelsea defender Cahill, club captain John Terry and assistant boss Steve Holland went to the hospital to check on Mason last night.
Chelsea defender Gary Cahill checks on Hull midfielder Ryan Mason after their clash of heads
Premier League and Football League clubs send best wishes to Ryan Mason
Mon, January 23, 2017
Premier League and Football League clubs have been quick to send their best wishes to Ryan Mason after the Hull City midfielder suffered a fractured skull against Chelsea
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Football clubs all over the country have sent best wishes to Hull City midfielder Ryan Mason
According to the London Evening Standard, Chelsea players Cahill and Terry and Antonio Conte’s assistant Holland spent time with Mason’s parents as the 25-year-old was still in surgery.
Mason has been inundated with messages of support after the incident that saw him carried off on a stretcher and receiving oxygen early on during Chelsea’s match with Hull.
Hull today revealed the player has started speaking again and wanted to thank those who sent him messages of support.
Gary Cahill and Ryan Mason clash heads at Stamford Bridge
“The club can confirm that Ryan has been visited this morning at St Mary’s hospital by club captain Michael Dawson, club doctor Mark Waller, head of medical Rob Price and club secretary Matt Wild,” a statement read this afternoon.
“Ryan has been speaking of the incident yesterday and will continue to be monitored at the hospital over the coming days where the club will remain in close contact with Ryan, his family and the staff at St Mary’s.
“Ryan and his family have also been extremely touched by the overwhelming support they have received and would very much like to thank all of those who have posted such positive comments both on social media and in the press over the last 24 hours.”
Hull players check on Ryan Mason after his clash of heads
Brain injury charity Headway praised the treatment of the England international.
Headway chief executive Peter McCabe said: "I was actually at the match and, while it was upsetting to witness the incident, it was encouraging to see the exemplary reaction of the medical teams.
"Headway has been critical of the way in which head injuries have been treated in many high-profile football incidents in recent years, but it is positive to see that lessons appear to have been learned."