Cahill was substituted for Mamadou Sakho after just six minutes against his former club as Willian initiated the visitors' scoring, but Hodgson described the night's most dramatic talking point as "very unfortunate."
Speaking in his post-match press conference, Hodgson said: "It would have been asking a lot I think [for Chelsea to stop play]. People react instinctively - you find yourself behind the defence in a really good position to create a goal chance, you carry on and take it.
"I think it would be unrealistic for me to suggest they [Willian] should suddenly put their foot on the ball and stop and run straight to Gary and see how he is. That’s not the way football is. It certainly was a very unfortunate incident that happened so early in the game and in the end it cost us a point - because that was the goal they won by. They won by one goal, and that was it."
Focusing on Cahill more closely, Hodgson provided an update on the Eagles' experienced centre-back.
"It’s a hamstring injury," Hodgson confirmed. "He’s obviously felt his hamstring give way. He’ll obviously be assessed and receive a scan but I’ll be very surprised if there isn’t a tear in the muscle.
"I’d be even more surprised with such a short period of time to play this season if he gets back to be a part of the four matches remaining."