Slaven Bilic insisted West Ham never stopped believing they could turn their season around as the Hammers thrashed Swansea 4-1 at the Liberty Stadium on Boxing Day.
The success in south Wales was West Ham's third win in a row in the Premier League - form which has seen them climb to 11th in the table after a difficult start to the campaign.
Andre Ayew set the ball rolling against his former club, netting his first for West Ham since a club-record switch in the summer, before goals from Winston Reid and Michail Antonio put the visitors in control.
Fernando Llorente gave the Swans a glimmer of hope late on, but Andy Carroll quickly added a fourth for West Ham in stoppage time to put the gloss on a performance that delighted Bilic, who insisted that he never doubted his side would turn around their fortunes.
"It was a really good performance," Bilic told Sky Sports. "We were compact when we needed to defend as a team, we were dangerous when we had opportunities. Maybe it was the best performance of the season. I am really pleased with everyone in the team.
"The first goal was really important. We always looked promising on the ball, and we knew we could hurt them. Of course the second goal is very important, and in a crucial moment.
"The key thing was that we never stopped believing. We kept training hard, and when we had those hard moments, when we had five extremely difficult games, against the top teams, we knew we had those two home games against Hull and Burnley.
"Those wins meant we could breathe a little bit."
Ayew earned a special mention from Bilic, who feels that his new striker has had plenty to overcome to get to this point.
"It is not just his goal, but his performance," Bilic added. "He had a really bad injury and now with a goal he can continue to improve."
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