WWE announced on Twitter that Corey Graves will be replacing JBL on commentary for Smackdown Live and Nigel McGuinness will be doing commentary for 205 Live and Main Event.
BREAKING: @WWEGraves will take over for @JCLayfield on #SDLive starting tomorrow; @McGuinnessNigel will step in for #205Live and #MainEvent!
— WWE (@WWE) September 4, 2017