When we first see Lucas in this episode, he is shaving. In the wide shot you can tell exactly half of his face is shaved. But in the closeup outside the house, there is no shaving cream above or below his lips. Also, when he steps out to the porch, you can see a couple of buttons are undone on his long sleeved undershirt. When Sam arrives, Lucasí undershirt is definitely closed moreómaybe only one button undone.
Also note how the edges of the front are folded down, like a wide V-neck. Then they go inside and the edges of the collar arenít folded down. Thanks Ann Marie for this page of bloopers!