Ricciardi made the announcement before Toronto's 5-3 win at Oakland. He said a medical examination determined that right-hander Halladay, the 2003 American League Cy Young Award winner, had no structural damage in his sore right shoulder and would not need surgery.
"The best way to describe it is he has a tired shoulder and needs to rest," Ricciardi said.
Halladay has a 7-7 record with a 4.35 earned run average. He has been bothered by the shoulder much of the season and was on the disabled list in June.
Pat Hentgen is scheduled to take Halladay's next turn in the pitching rotation.