Alexander played the cameo part of Toby Powers in the final ever episode of HBO’s “Eastbound & Down”, which aired on US television in November 2013.

From Vulture interview with co-creator Jody Hill.

Where did the idea to cast Lindsay Lohan and Alexander Skarsgard as Kenny’s kids come from?
God, where did we get the Lindsay Lohan idea? I think we wanted to give people something to talk about, but it also fits. It’s Kenny’s idea. He’s writing this screenplay, so it would make sense that he would cast Lindsay Lohan. We just put ourselves in Kenny’s head and asked whom we thought he’d want to play his daughter. And for Alexander Skarsgard? Maybe he was like, “I love True Blood.”

You can watch Alexander’s scenes here