Baltimore Orioles pitcher Steve Bechler died Monday of heatstroke, less than 24 hours after complaining of dizziness during a spring training workout.

The 23-year-old Bechler was pronounced dead at Northridge Medical Center, where he had been in intensive care overnight, team officials said.

He was pale and feeling lightheaded Sunday while completing his final conditioning run at Fort Lauderdale Stadium. The initial diagnosis was heat exhaustion and dehydration, but his condition worsened after he arrived at the hospital by ambulance.

An autopsy will help determine whether Bechler had been taking the dietary supplement ephedrine, which has been linked to heatstroke and heart attacks.

Broward County medical examiner Dr. Joshua Perper acknowledged a published report that a bottle of a supplement containing ephedrine was found in Bechler's locker.

Regarding the bottle, Perper said: "My understanding is it exists, but we don't have it."

William Goldiner, the Orioles' team physician, said Bechler died of "multi-organ failure due to heatstroke."

"He would rebound at times. They thought they were getting ahead of it, and then another organ system would fail," Goldiner said at a news conference.

Bechler's body temperature reached 108 degrees, he said. The National Weather Service said that at noon Sunday, the temperature in Fort Lauderdale was 81 degrees and the humidity was 74 percent.

"Steve was a tough guy; he was a competitor," manager Mike Hargrove said. "I didn't know him that well, but I knew him well enough to know he loved the game and loved to compete."

The 6-foot-2, 239-pound Bechler, a third-round draft pick in 1998, made his Major League debut last September, going 0-0 with a 13.50 ERA in three relief appearances. He was expected to begin this season with the club's new Triple-A affiliate in Ottawa, Canada.

He spent most of last season at Triple-A Rochester, N.Y., going 6-11 with a 4.09 ERA in 24 starts.

The players were briefed about Bechler's condition during a clubhouse meeting before Monday's workout. They were summoned inside a short while later and told of his death.

"Everybody was in shock," Orioles pitcher Rodrigo Lopez said.

On Sunday, Hargrove said he could tell Bechler wasn't feeling well toward the end of the conditioning run.

"He was about 60 percent of the way through it when we noticed that he was a little white-faced," Hargrove said. "He was leaning against a fence ... which isn't unusual when guys get tired. We put him on a cart and brought him in and called the paramedics."

Last season, baseball was stunned by the death of St. Louis pitcher Darryl Kile, 33. He died in June from blocked coronary arteries while in Chicago for a game.