Town will be without Luke Garbutt and Teddy Bishop due to injury - in addition to the suspended Gwion Edwards - for Saturday’s trip to Sunderland but Emyr Huws is available having missed last week’s defeat to Peterborough.
Garbutt, Town’s third-top scorer with six goals, was subbed in the first half of last week’s 4-1 loss to Peterborough and Lambert says the on-loan Everton man won’t be fit for the visit to Wearside.
"It’s not as bad as we first thought, so that’s the plus side of it. But he’s out for this one,” he said. "It’s his thigh, he’s got a thigh strain.
"He’s been great. I think his game has got better and better, his assists, his goals and his delivery. It’s certainly a blow, but it’s somebody else’s opportunity.”
Lambert, who will almost certainly pick Myles Kenlock at left wing-back, says Tuesday’s trip to AFC Wimbledon will also probably come too early for Garbutt: "I think he’ll be a doubt that one.”
Edwards will miss two games having picked up his 10th booking of the season against his old club last week with Lambert having been pleased with the way the Welshman has grown into the wing-back role.
"It’s somebody else’s opportunity,” he said. "That’s football and I don’t caught up in the disappointment of it, you need luck in football to stay clear of injury and suspension, and you know the consequences if you do get suspended — you’re sitting the stands. But I don’t get caught up in it. It’s somebody else’s opportunity."
Janoi Donacien will replace Edwards at right wing-back and Lambert has no qualms about starting the St Lucia-born defender.
"He’s done fine,” he added. "Janoi only found his way out of the team because his injury up at Lincoln that day and Gwion had done really well and whatever personnel we put in there or system we’re playing we expect people to go and perform.
"You have to [take your chance when it comes along]. I always think it and I always say it, the day you stop looking over your shoulder as a footballer then you’re finished.
"You’ve got to look over your shoulder because somebody has to breathe down your neck to take your place. Whether it’s a young guy or experienced guy, you have to look over your shoulder or else you’ll become complacent.”
He says Kane Vincent-Young remains on course for a return after his groin surgery at the end of February.
"He’s doing okay,” Lambert continued. "He’s doing better than okay actually, he’s doing really really well and hopefully, we’ll see him — hopefully — at the end of the month.”
Asked whether any involvement at that stage would be in an U23s game, Lambert said: "It depends how he feels. He’s a naturally fit guy and he’s really looked after himself, he’s got no problem with weight or anything like that at all, so hopefully he’ll be okay.
"He was excellent before he got injured. His injury was a blow because of the way he was performing and he settled in really well. But he’ll be back and hopefully by the end of the month.”
Huws missed the game against Posh with an ankle injury he had suffered at Rotherham on the previous Tuesday but Lambert says the Wales international is now fit.
However, Teddy Bishop, who picked up a knee problem in training, isn’t yet ready to return to the squad.
"Emyr’s available for it, Bish is not,” he said. "Jon Nolan’s wife just had a baby the other day, so we’ll see how he feels, he’s been in seeing her and congratulations to them, I think that’s really good. So, we’ll see how everybody is.”
Lambert says he’s not sure whether Bishop might be available for the visit to the Dons on Tuesday.
"I don’t know,” he added. "Hopefully, he’ll train on Monday and then we’ll see how he is. But with Bish again, it’s the same thing, he has to stay fit.”
Defender Josh Earl could return to the 18 having suffered a cheekbone injury in training.
"We’ll see how he is with that,” the Blues boss continued. "He’s doing alright, Josh. He’s upbeat with it, so we’ll see how he his.”
Asked whether the on-loan Preston man might have to play in a mask, he added: "I think they’re looking at that at the minute, it’s whether you can wear it, I’m not too sure a lot of people like wearing them.”
Quizzed on whether youngster Armando Dobra, the subject of a Brighton bid close to the end of the transfer window, can play a part in the final months of the season, Lambert said: "He needs games, Dobs, he needs games.
"There are other guys ahead of him and he knows that himself, so he’s only a young kid who I think has got really good potential.”
Lambert’s squad suddenly feels somewhat stretched but he reiterated that the absences will give someone else a chance.
"That’s football,” he reflected. "It’s somebody else’s opportunity. I don’t care how young you are or how old you are. If you’re a footballer, you’ll be ready when you’re picked.”