Its a wild idea, but if a defence sits back it might help to have more than one striker in the box.
Or we could just keep passing it around the area while he watches & then have a go at him for scoring the 0 chances he's getting next to the 3 defenders marking him. I mean, hes probably just really tired. Lets try another guy in the same position. Hang on, thats not working. Lets change someone else, Lallana's playing ok whilst having 0 goal threat, lets change him for someone playing really poorly also with 0 goal threat. I reckon that takes our goal threat up.