Tyrick Mitchell scored twice either side of the interval before Ben Chilwell struck a dramatic late winner on his first game back at the club since rejoining Crystal Palace on loan earlier in the week, capping a memorable second-half turnaround in south London. Fulham's Cesar Palacios and Gonzalo Garcia, both summer arrivals from Real Madrid, had given Álvaro Arbeloa's side a first-half lead before Palace responded.
"We want to keep the spirit of the win. But we are aware of our performance, especially in the first-half because the mindset of the team was low," Sage said.
"We changed these things in the second-half and at the end we came back twice. It was a good thing because we need both the confidence and points to work with less pressure."
Asked what he had said to his players at half-time, Sage revealed he had spoken directly to two individuals.
"I just wanted to be honest with them and spoke to the two players who made a mistake in the first-half, Jaydee Canvot and Chris Richards, and told them that we would need them," he said. "We needed them to play with bravery in the second-half. But they changed I think and that was really important."
Sage's side started summer signings Axel Disasi and Quinten Timber for the first time, with the Frenchman keen to stress the importance of integrating his new arrivals as the season progresses.
Arbeloa, whose Fulham side have now lost narrowly in back-to-back Premier League matches, felt his team did not deserve to leave Selhurst Park empty-handed.
"I think we didn't deserve to lose this game. I think my players did everything, good attitude, they were brave, so many chances to score more goals. They took their chances, in the end football is about that," he said.
He was particularly frustrated by the manner of Palace's second goal.
"We were really unlucky in this goal, we had many chances also we were very unlucky. Good effort from Gonzalo, that's the spirit I want from my players, the striker making a sprint to try and save a goal. With that spirit and character, if we play in this way, the victories will come."
Despite the result, Arbeloa was quick to praise individuals within his squad.
"We did many good things to win the game, it was similar against Chelsea but we lose. For the players it's a difficult situation, difficult moment, but I am very proud of them," he said. "Cesar Palacios and Gonzalo Garcia both had a great game, Cesar scored a goal, and for Gonzalo another great performance."