The Argentine defender helped Garry Monk's side, who finished the match with 10 men following the dismissal of Jonjo Shelvey, keep a clean sheet at Goodison Park on Saturday to clinch a point which leaves them sixth in the table.
The Swans captain told the club's website: "It was his best game for us so far. He read everything against Everton, he was a tower of strength and he was excellent in the air too.
"I'm very comfortable playing next to him. He's settled in well since coming to us from Napoli, and I think he has a very good understanding of what to expect in the Premier League, as well as what is expected of him.
"We spoke a lot in pre-season about tightening up defensively. I think it's evident in our performances and clean sheets that we have done that. We are putting our bodies on the line to block shots and crosses. As a defender that is your job, and everyone deserves a pat on the back for the performance against Everton."
Fernandez was sent off in the Capital One Cup earlier this week, but Swansea successfully appealed the red card.