The 22-year-old began the game on the bench at the Amex Stadium but was brought in as a substitute in the 71st minute, just after Forest had leveled the score at 2-2.
12 minutes later Brighton were trying to break at pace with Pedro and Morgan Gibbs-White slid in heavily, taking the ball but also the man.
Gibbs-White was shown a second yellow card for the challenge amid fury from both benches as Brighton boss Fabian Hurzeler and Forest manager Nuno Espirito Santo were both sent off.
Pedro finished the game but was not moving freely and Crofts was not sure of his condition after the match after the forward missed the last game against Ipswich due to injury.
‘The tackle on Joao looked like it wasn’t a great tackle,’ Crofts told . ‘We were upset with it. The reaction is to see what the referee does. I didn’t see it because I was communicating with a player. Next thing I saw the red cards to the managers.
‘Joao took a nasty hit. Hopefully he’s okay.’
On the chaotic scenes after the challenge from Gibbs-White, Croft added: ‘Late in the game where we’re trying to push to win the game and there’s a foul right by our bench. The player is going for the ball but it felt like a foul. Their bench felt differently.
‘I didn’t see too much of it but the referee sent the managers off. I’m not 100 per cent sure [why Fabian Hurzeler was sent off]. I haven’t seen it back. I’ll ask him when I see him. We’re frustrated. We felt we should have won the game. We created lots of chances. We probably would have wanted to create more chances.’
Forest took the lead in the first-half through a Chris Wood penalty but quickfire goals from Jack Hinshelwood and Danny Welbeck before the interval put the Seagulls ahead.
Ramon Sosa equalised on 70 minutes to leave the Brighton camp frustrated.
‘We are bitterly disappointed not to get three points. We created enough chances to win the game. We’re frustrated and maybe tempers were frayed,’ said Crofts.
‘Hopefully we can learn a lot from the last two games at home. But we’re still unbeaten so there’s a lot to be positive about.’
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