Jim Ross commented on Brock Lesnar announcing his retirement from mixed martial arts after losing in the opening round to Alistair Overeem in Las Vegas, Nevada at UFC 141.
"Brock Lesnar to WWE rumors rampant. Always said IF Brock returns it would be for a one off appearance. Now's NOT the time," Ross tweeted.
He continued, "I find it HIGHLY IMPROBABLE that there is an even remote chance of a Brock Lesnar vs Undertaker match at WM28. IE..ain't gonna happen. Calling Oliver Stone..please report to rumor central/fantasy booking department to write Lesnar to WWE storyline. No rush. 2013 will do."
As noted earlier, there are absolutely no plans for Brock Lesnar to return to WWE at the current time. He's still under contract with UFC. Could it happen in the future? Of course but it won't be anytime soon.