Bafetimbi Gomis and Andre Ayew both scored for the second successive game as Swansea built on their impressive opener against Chelsea with their first victory of the season.
Newcastle found the Welsh side hard to compete with throughout the afternoon, with Daryl Janmaat receiving his marching orders just before half-time as Jefferson Montero ran the Toon defence ragged.
“We dominated the whole game from start to finish,” Monk told reporters post-match. “When the red card does come it impacts on the dynamic of the other team more and they sat back after that.
“We were very professional in the second half and made sure we won the game with a clean sheet.
“We started well, got a fantastic goal. We were very professional after the sending off and we could have had more goals.”
Discussing Janmaat’s red card further, with the Dutchman sent off for two bookable offences, Monk said referee Mike Jones “made the right decision”.
“The red card didn’t change the game, we were dominating before that,” Monk told Sky Sports.
“If anything it made them more narrow and difficult to beat. We were never in any danger today. We defended and attacked very well.
“Jaanmat had a couple of lunges in before the red card, so he was running the risk and the referee made the right decision. Credit to him for that.
“Even before the sending-off we were playing some great football and were in complete control of the game. It was a fantastic goal from Gomis that set us on our way and we never looked back.
“It became difficult second-half as they defended very deep and made the game narrow. Then the gaps become less easy to find but I thought we were very mature at that point. We were in complete control of the game and moved the ball very well.”