Three Lions could be facing another injury problem after the 26-year-old collided with Joe Hart in the first half against Belgium and had to have treatment at Wembley
The Chelsea defender was replaced by Joleon Lescott after colliding heavily with team-mate Joe Hart following a push from Belgium's Dries Mertens in the 17th minute.
Cahill was substituted immediately and subsequently underwent an X-ray on his jaw to establish the severity of the injury.
Manager Roy Hodgson confirmed the news in the post-match press conference: "Cahill [is] having a CT scan as we speak... if he has fractured jaw, which is a distinct possibility, we [will] lose him for Poland."
“I don’t think I’ll have the result of that for a couple of hours. If he hasn’t fractured it, he will be okay to go.”
Mertens' foul caused the collision and Hodgson was unimpressed with the incident adding: “I wasn’t too happy about it. Those nudges, if you’ve been a goalkeeper of defender, you take very unkindly to that kind of challenge.
“He got a yellow card for it but the consequences got be a lot more serious for us.”
England went on to win the match 1-0 courtesy of a first-half goal from Manchester United striker Danny Welbeck, meaning Hodgson has now won both of his first two games since taking the reins of the national side.
However, the injury to Cahill will concern the former Liverpool manager who has already lost John Ruddy, Gareth Barry and Frank Lampard from his original Euro 2012 squad due to injury.