So long as it’s ratings hit a certain number, Charlie Sheen’s new sitcom “Anger Management” was going to get a 90-episode back-order.

FX just announced that – and despite the dip in ratings for the sitcom (being blamed on the Olympics) – the show has got the back-90.

The tenth episode of the show marked Martin Sheen’s debut on the show. He’ll rejoin son Charlie for at least 20 of the 90 episodes to come.

Personally, I’m not Gary Busey-crazy on the show – I watched a couple of episodes before losing interest – but it’s a big win for Sheen, particularly giving what a huge gamble it was for him skipping out on “Two and-a-half Men” and hoping to find lighting in a bottle again here.

Charlie Sheen has said “Anger Management” will be his final hurrah in acting; what that means for the long-proposed “Major League 4″ I don’t know, but hopefully he’ll squeeze in some film work on his hiatus from the FX comedy – just as he has done this year, filming “Machete Kills” and “Scary Movie 5″ while on break.