Magpies number 1 Dubravka was only available for selection half way into the current Premier League campaign as he was sidelined with a heel bone injury.
Bruce asked Darlow to step up between the sticks in the Slovakian’s absence and he has since leapfrogged the 32-year-old in the pecking order.
The Magpies boss, who lauded Dubravka for his professionalism, admitted the shot-stopper is not content with his lack of game time.
However, Bruce stressed that he is happy with how Darlow has performed on the pitch so far this season, explaining he needs that competition for places between both custodians at St. James’ Park.
“He is [Dubravka] being very, very professional about it and understands”, Bruce told a press conference.
“That does not mean to say he is happy, which I would not expect him to be.
“I have got a situation- we have got another very, very good young goalkeeper [Freddie Woodman] down in Swansea doing very well too.
“So, in that area of the pitch, we are extremely good.
“And of course, with a goalkeeper, you can only pick one of them.
“At the minute I have stayed with Karl because I think he deserves to be [playing].
“All season we have said how well he has done, and the one thing I need to have is to create that competition.
“So Karl has got the nod at the moment, but as we have seen in football things can change very quickly.”
Darlow has four clean sheets to his name in 24 Premier League outings and will have to be at his best should he seek to add another to his tally as Newcastle are set to face a tough challenge away at Manchester United on Sunday.