Australia's Tye Simmonds has been forced out of two events this year with illness.

Australian rising star Tye Simmonds was forced out of Saturday’s fifth round of the Lucas Oil AMA Pro Motocross Championship, missing his second race weekend in a row.

JDR/J-Star/KTM’s Simmonds has been diagnosed with ‘rhinosinusitis’ and bronchitis, marking the second time he has been forced out with bronchitis this season.

On that occasion, Simmonds was forced out of the San Diego round of the AMA Supercross series.

“I am taking this weekend off to rest and recover,” the 19-year-old AMA rookie said.

“I have also scheduled more intensive tests for next week that will hopefully determine why I have been so susceptible to contracting this illness.”

Team manager Nathan Ramsey understood Simmonds’ situation, not placing any pressure on him to return too quickly.

“We will wait to hear from the doctors and make our decision on when Tye should return to racing based upon those results,” Ramsey explained.

“We definitely don’t want to jeopardize his health by sending him to a race when he is not 100 percent physically.”