Steve Asmussen has been notified of a drug overage, Daily Racing Form reported June 25.
The paper, on its Web site, said Asmussen would be officially served notice June 26 that the filly Timber Trick, who broke her maiden at Lone Star Park in Texas May 10, tested positive for the anesthetic lidocaine.
Daily Racing Form reported that attorney Karen Murphy, who is representing Asmussen, said a request to the Texas Racing Commission to have a split sample tested was denied.
The 3-year-old filly is owned by Gainesway Stable. She has run since, finishing second June 6 at Lone Star.
Asmussen served a six-month suspension in 2006-07 after a positive for mepivacaine in Louisiana. At the same time, he served a similar suspension for an acepromazine positive in New Mexico.