ARLINGTON, Texas -- Texas Rangers pitcher Ryan Glynn is expected to resume workouts Saturday after medical tests determined the cause of his sudden fainting and that he had no lingering effects.

Dr. David Hunter, the Rangers' internist, said Wednesday that Glynn could be more susceptible to fainting again under certain conditions, but there is nothing wrong with the pitcher's heart. Glynn had never experienced such a problem before.

Glynn suddenly passed out after being taken out in the fifth inning of Friday night's game against Boston. He had thrown 95 pitches in a game that started in 98-degree heat.

Hunter said dehydration is a condition that could have provoked the fainting.

Glynn (3-2, 4.70 ERA in nine starts) was hospitalized overnight and put through an initial series of tests after passing out in the dugout. He was later placed on the 15-day disabled list effective Saturday as more tests were done to determine the cause.

Hunter said Glynn, 25, would have to clear a final physical examination Friday before being cleared to pitch again.