Keep playing well and keep scoring goals will give Lambert no other option than to play him. It's that simple and I'm sure Darren knows the situation.
I'd have started with Benteke and Gabby yesterday after the midweek win. I do think Bent maybe should have come on a little earlier than he did though. Regarding Benteke, to me it seems he needs a goal to get himself in the game, he was trying too hard at times yesterday. He'll be ok though but it might be next season when he clicks.