Highlights here: Sky Sports
Huddersfield boss David Wagner will view the match video before deciding whether to appeal against goalkeeper Danny Ward's red card.
He said: "I haven't seen the video again but Danny says he touched the ball with his shoulder, not his arms or his hand.
"If we can clearly see the referee made the wrong decision, then we will appeal."
Wagner, who has been asked by the EFL to explain his team selection after making 10 changes for last weekend's 2-0 defeat at Birmingham, made nine changes for this game, bringing back most of his first-choice players.
"What happened with Danny Ward is why it was good to bring in some fresh players for the Birmingham game," he said.
"Joel Coleman played in goal against Birmingham and has had more minutes to work on his body shape and fitness."
Wagner said his players lacked concentration and focus but were anxious to get on with the play-offs.
"We were not switched onto the game and, even for me, it's not been easy to finish one competition and get ready for another," he said.
"Now the competition that counts is in front of us.
"It's been a fantastic achievement but we will not go into the play-offs as favourites.
"We like the underdog role. Huddersfield Town are still in the race but we are humble as always."
Cardiff boss Neil Warnock is eager to build for next season after guiding his side to a 12th-placed finish.
"I have steadied the ship and I have not spent a penny yet," he said.
"I have agreed a couple of fringe players but we are looking to sign three or four who can really help us.
"Now it's time for a rest because the players have worked their socks off. I want the players to enjoy it with me. We don't train every minute of the day but I want them to die for me when they get out on the pitch."
Warnock said the all-Yorkshire play-off semi-final would be "intriguing" but added: "For me, Fulham will go up. They are the best team, but they probably don't have the best defence."