Triple Crown hopeful I'll Have Another jogged around the 1-mile Belmont Park oval for a second day in a row and is scheduled to resume galloping on Friday.
The Kentucky Derby and Preakness winner will attempt to become the 12th Triple Crown winner in the Belmont Stakes on June 9.
The colt's assistant trainer Jack Sisterson said Thursday "he gets over the track fantastic, he looked super, his energy level is high and he's doing everything we want to see him doing."
Sisterson said I'll Have Another will pick up the pace with a gallop on Friday.
The last horse to sweep the Derby, Preakness and Belmont was Affirmed in 1978.
Also, Belmont contender Union Rags worked five furlongs on Thursday in 1:01 at Fair Hill, Md.