"He feels good and he's ready to go," Williams said.
Williams said the thought is that Gonzalez will be able to rejoin the Nationals after his one rehab start, but it will depend on how the left-hander feels after his start and how he pitches on Friday.
"It's fairly quick and he hasn't gotten to 100 [pitches] yet," Williams said. "So we'll have to see."
Gonzalez was placed on the 15-day disabled list on May 18. He threw a three-inning simulated game on Sunday morning and afterward reported feeling great to Williams.
Daniel Popper is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.