Carlos Carvalhal admitted his gamble backfired as Swansea sank back into the relegation zone after a 4-1 defeat at Brighton.
The Swans boss threw on attackers Andre Ayew, Luciano Narsingh and Tammy Abraham with his side trailing to Glenn Murray’s first-half penalty.
But Brighton simply exploited the gaps at the back as Murray’s second, and goals from Anthony Knockaert and Jurgen Locadia ended the visitors’ 10-game unbeaten run.
“When we were losing 1-0 I was thinking we must change things, so we put Ayew in attack,” said Carvalhal.
“We took the risks because we were not happy to lose and we wanted to try to win. So we put Luciano and Tammy on.
“It was a big bet and with a big bet you can win lots of money or you can lose lots of money.
“We knew if we scored one we could win, but we also knew if they scored another on the counter-attack it would be difficult, and that’s what happened.
“That’s football, that’s the life of a manager. If it works the manager is a genius.
“We tried everything to try to win, but Brighton deserved to win. We lost the gamble.”
Brighton went ahead in the 19th minute after Mike van der Hoorn caught the back of Murray’s leg, sending the striker tumbling to the deck.
Murray stepped up and confidently tucked away the spot-kick, sending Lukasz Fabianski the wrong way.
Both sides hit the woodwork before the interval, Lewis Dunk thumping a header against the crossbar and Jordan Ayew firing against a post.
But moments after Abraham’s introduction, Murray swept in his second, and Knockaert latched onto a Pascal Gross through-ball to make it three.
Swansea pulled one back when Abraham’s shot was deflected in by Dunk, but Brighton substitute Locadia had the last word in the final minute.
The World Cup may be a pipe dream for 34-year-old Murray, but he now has 10 Premier League goals this season and only three Englishmen – Harry Kane, Raheem Sterling and Jamie Vardy – have scored more.
“To score 10 for a side like us, who we know are going to find it difficult to score goals in the Premier League, that is some achievement,” said Albion manager Chris Hughton.
“Glenn has been good for us generally, but if I picked out the last five or six games he’s been great, not only his goals but what he is putting in for the team.”
The victory moved Brighton four points clear of the drop zone and Hughton added: “It’s very pleasing.
“We went through difficult periods today, but as the game opened up we really capitalised.
“It’s probably the game this season where we could have scored more, and there aren’t too many occasions you could say that.”