The 28-year-old scored Madrid's third goal just past the hour-mark to end a run of back-to-back draws in La Liga and Navas lauded the Welshman.
"He's an excellent player and he always helps us," Navas said.
"Despite what people may say, he always works hard and puts a shift in, and today [Sunday] he got his reward.
"Nobody likes to hear people speaking negatively about anyone, but he's a professional, and he has confidence in his ability and knows the team is behind him.
"He showed his quality [against Sociedad]."
Navas, whose Madrid are four points adrift of leaders Barcelona, added: "I'm happy to be playing alongside the best in the world, it's unbelievable.
"We're a team who always give it our all and sometimes things go well and other less so, but we're in this together and that's beautiful, it’s great to be part of it."
Madrid defender Dani Carvajal also lauded youngster Borja Mayoral following his goal in San Sebastian.
In the side with Karim Benzema and Cristiano Ronaldo absent, the 20-year-old forward opened the scoring in his first La Liga start since April 2016.
"We have a very big squad, and it is clear that Mayoral is perfectly able to help us and score goals," said Carvajal, who signed a five-year contract until 2022.
"We knew that if we lost then we would be seven points off the pace and it was not an easy game with a lot of players out away from home, but the team showed character."