A's reliever Rosenthal sees thoracic outlet syndrome specialist

A's Trevor Rosenthal

More tough news for the Athletics.

On Tuesday, reliever Trevor Rosenthal visited Dr. Gregory Pearl in Dallas after landing on the 10-day injury list heading into the season. Dr. Pearl specializes in thoracic outlet syndrome.

“He flew to Dallas to see a Dr. Pearl today, on his right shoulder,” A’s manager Bob Melvin said Tuesday. “We do not have the results on that, I probably will have that for you tomorrow.”

The Athletic’s Ken Rosenthal said if Rosenthal were to require surgery, it likely would sideline him for three to four months

Thoracic outlet syndrome, according to Cleveland Clinic, describes "a group of disorders that occur when there is compression, injury, or irritation of the nerves and/or blood vessels (arteries and veins) in the lower neck and upper chest area.”

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Rosenthal had initially been taking medication for his shoulder when he landed on the IL, but Melvin said the reliever's visit didn't necessarily mean the medication was ineffective.

“We were always going to target this particular doctor to take a look at him,” Melvin said. “It was more just not bouncing back from the outings he had toward the end of spring training so this is the guy that they target to go talk to. I think he’s potentially talking to him right now, but no results yet.”

The A’s signed Rosenthal to a one-year contract in February after his phenomenal 2020 season. With the Kansas City Royals and the San Diego Padres, Rosenthal posted a 1.90 ERA with 38 strikeouts in 23 2/3 innings.