Shinsuke Nakamura has basically been taking the place of John Cena on Smackdown, wrestling dark matches after the live program ends. He has been one of the brand’s key babyfaces and is expected to stay in that role moving forward.
One of the main reasons WWE has him wrestling on dark matches is because the hope is that he is enough of a draw (like Cena) to keep the crowd from leaving before the 205 Live show begins.
Source: Wrestling Observer Newsletter