The Northern Ireland international, signed on a season-long loan from Burnley, was a redoubtable last line of defence as Wednesday extended their unbeaten League One sequence to 11 matches - on a night when they played the final 21 minutes with ten men following the dismissal of midfield enforcer Massimo Luongo.
Peacock-Farrell has hit back strongly from making one or two high-profile errors in the autumn, but Moore insists his quality has never been in doubt.
Moore, whose eighth-placed side are currently two points below the final team in the play-offs in Plymouth Argyle, said: "I said at the start of the season when he came to the club that he is the best goalkeeper in the league.
"The clean sheet will have done him a world of good. He has performed heroics (at Portsmouth) and he showed why he is at the level and standard that he is.
"Some of the saves weren't easy, but they were made to look routine. His positional sense was so good.
"At the end when they were putting the ball in the box, he had to really stretch for them to relieve the pressure. I thought his game management was excellent at the end. He had to be big.
"Teams put a lot of balls into the box in this league but I thought he was excellent. He had to perform and he did and we are really grateful for him.
"Credit to him and we move on to Crewe on Saturday and hopefully we will get one or two players back."
Meanwhile, Moore insisted he had no complaints at the sending off of Luongo for a lunging challenge on Rohan Curtis.
The Owls boss, among the list of four nominees for the League One manager-of-the-month accolade for November, added: "I have looked at the footage. Although he gets a slight tug, he was out of control when he lunged for the ball. He came out on top of the ball and caught the player so I have got no complaints."
Bidding for the November gong along with Moore are Pompey manager Danny Cowley, Wigan chief Leam Richardson and Oxford United boss Karl Robinson.