The track says the 3-year-old was timed in 53.80 seconds on Wednesday during a leisurely workout.
Trainer Jason Servis didn't immediately respond to a text message from The Associated Press seeking comment. Servis hasn't indicated where Maximum Security will race next.
Monmouth Park officials hope Maximum Security runs in either the Pagasus or the Haskell Invitational, both at the Jersey Shore track. The Pegasus is in June and the Haskell in July.
Maximum Security arrived at Monmouth Park on May 7, three days after becoming the first horse to be disqualified after finishing first in the 145-year history of the Kentucky Derby.
Servis trained him for one day and then decided to give the colt more rest.
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