Temporary Injury with only 5 players.

[Eastshire]

I had this happen over the weekend.

Team A has 6 players, one of whom has fouled out. A1 goes to the floor with an apparent injury and the game is stopped and the coach is beckoned. A1 is ready to participate after collecting his wits.

If A does not choose to use a timeout to keep A1 in the game, can they continue with 4? Since A1 is clearly able to continue does A have to take a timeout to keep him in the game to maintain 5 players on the court? Other thoughts?

I thought there was a case play on this but if there is, I'm missing it.