The alternate who will take his place is Anthony Saraceno of Cortland, New York, who competed in sectional qualifying on June 11 in Bolton Landing. Saraceno shot 70 at Sagamore Golf Club.
Nicklaus has had back pain for over a year and has played tournament golf sparingly in 2002. He made the cut at the Memorial on the PGA Tour and qualified for the weekend at the Senior PGA Championship but pulled out before the start of the third round.
The Golden Bear won two U.S. Senior Opens - in 1991 and 1993. He owns two runner-up finishes with four top-10s. Last year, Nicklaus tied for fourth behind champion Bruce Fleisher.
Nicklaus is the second player to withdraw from the U.S. Senior Open Monday. J.C. Snead pulled out because of exhaustion after winning the Greater Baltimore Classic over the weekend.
The U.S. Senior Open kicks off Thursday at Caves Valley Golf Club in Baltimore, Maryland.