KARLEIGH Osborne is ready to step into the breach against Leeds United on Saturday after Mark Beevers was sidelined by a knee injury.
Beevers sprained medial ligaments during the Lions' 1-0 victory over Charlton last weekend and could be out of action for up to eight weeks, although he is unlikely to need surgery.
And Osborne, who has been on the bench for the last two matches, is determined to seize the moment if boss Steve Lomas selects him for the clash against the Yorkshire club.
He said: "Obviously it's not good that Beevs has picked up an injury – although it could have been worse – but it might give me the chance to show the gaffer what I can do. If I'm given that chance, it's up to me to take it.
"I'll be working hard in training this week, as I have been doing since pre-season, so that I'm ready for that opportunity. If I'm called upon on Saturday, I will be ready for it – there is no doubt about that.
"I had been thinking I might have to go out on loan and play some games, but there's a possibility I might get given a chance here. I need to a regular run of games and hopefully prove myself to the manager and the fans that I'm good enough to play in a Championship team."
Osborne, who made 16 appearances for Millwall last season, is yet to play a minute of competitive action under Lomas – so a return against Leeds at The Den would be a real baptism of fire.
The 25-year-old added: "Sometimes that can be better for you – a big atmosphere, with the fans right behind us and especially off the back of two good results.
"It's been frustrating for me so far because I just want to play football, but the gaffer has had to work out what his best team is and he's picked who he's picked. I've had to bide my time and wait for my turn.
"It would be great go out there and prove my worth in a game like this. It's all starting to click now – the gaffer has come in with some new ideas and it's taken us a while to get going, but I think that's happened now."
Lomas admits he faces a tough choice as to whether to give Osborne the nod – or recall Danny Shittu, who he dropped from the squad last week.
"We are disappointed for Mark because he was looking good, but it's an opportunity for somebody else," said the Lions boss.
"We have either Danny or Karleigh to come in. We'll have a look at them in training and make a decision. We have three games in seven days which is tough on the squad, so that is something to consider as well.
"Both of them are right-sided and you would prefer a left-footer in there to replace Mark, but we've got to get on with it and it's a chance for one of them to stake a claim."