Lambert confident goalscorer Helenius can play his part
Kozak, who has generally been the go-to forward on the bench when Christian Benteke has started, broke his leg in training.
Striker Helenius came on against Sheff Utd and impressed with good hold-up play and a well-taken goal late on.
Lambert, despite the loss, was delighted to see Helenius on form in claret and blue.
And the boss insisted that Helenius can come good in the coming weeks and months ahead.
He said: "There's a chance for Nicklas to stake a claim.
"Nicklas did well when he came on. If there's one plus from the game, it was Nicklas coming on and scoring his first competitive goal.
"He has a bit of a hard time since he's been here. But he's a really lovely guy. He's a nice guy.
"It was a good goal. That will give his confidence the world of good.
"It's taken him time to adjust.When you're that young and you're trying to get to the level, some hit the ground quicker than others.
"I was delighted with him scoring the goal."
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