Striker Bent has been replaced by ?6.5million summer capture Christian Benteke in the starting line-up for the Barclays Premier League games with West Brom and Tottenham. There have been reports that Lambert and Bent, who has also been axed from the England squad, are not on speaking terms.
But Lambert is adamant the duo enjoy a healthy relationship although he understands Bent's frustration at losing his spot. The former Norwich boss said: "I've never had a problem with Darren. I have a laugh and a joke with him. Of course, I understand people get frustrated when they are left out. You'd be more worried if they weren't."
He continued: "But he has not been knocking on my door. There was never a problem.
"As for people saying we are not talking, I don't worry because I know it's not true.
"Like I said, we have a laugh and a joke and there has never been that problem.
"I try to be fair and honest with everyone. I don't rule with fear if that is what people think. I treat people the right way and respect them. I don't do anything untoward."
Lambert added: "You wouldn't take Darren's selfishness away from him because he is a goalscorer and that's what he does best.
"But my job is to pick a team that will win us a game. That is my job and that's what I try and do for this football club.
"It will be the same for everyone. I trust the lads to perform. That's the great thing I've got but I can't keep everyone happy all the time. It's a decision I'll make."