The Swans, who travel to Wembley Stadium next Sunday to face Bradford City, were hammered at Anfield in what was their eighth loss of the season.
"Today - nothing. It's the first game where I've seen that for a long, long, long time, I think since September," Laudrup told Sky Sports News.
"So a part of the excuse could be the head was already at Wembley but we have to live with this result and it's not nice."
The loss has seen Swansea slip down to eighth place in the Premier League table.