Zambrano, who earned his fifth win of the season by beating the New York Mets 9-3 on Thursday, complained of a stiff neck after the game. After undergoing an X-ray, Zambrano was told by Dr. Steven Gryzlo that the discomfort was coming from a knot in his neck and is mostly muscular.
"I usually sleep with my head turned that way like when I'm watching TV," said Zambrano, who has been experiencing stiffness in his neck for the past three or four starts. "So I guess I'll have to turn it the other way."
Zambrano said he will have massage therapy and will not miss a start.
"Nothing to worry about," Zambrano said. "The doctor said just to keep doing my exercises and massage treatment. it will be OK."
That's good news for the Cubs, who have three-fifths of their rotation on the disabled list.
Matt Garza was put on the DL on Monday with a sore elbow. Randy Wells and Andrew Cashner went on the disabled list April 8, but Wells is scheduled to return Saturday after straining his right forearm April 4.
Zambrano allowed two runs -- one earned -- in six innings against the Mets and went 3-for-3 with a double and RBI.
Bruce Levine covers baseball for ESPNChicago.com and ESPN 1000.