As Rich Hill continues to throw, Dodgers unsure about what’s causing his blister

On Tuesday afternoon, two days after irritating a blister on his left middle finger, Dodgers pitcher Rich Hill went outside to play catch. He distanced himself about 90 feet from his target. He wore a bandage over his damaged finger for the duration of the exercise.

After dealing with Hill’s blister for two months in 2016, the Dodgers are attempting to solve the problem once more. Despite lengthy study of the issue last season and this past winter, the team has been unable to determine why Hill is so susceptible to blisters, president of baseball operations Andrew Friedman explained.

“The most confounding part is that we’re not able to wrap our arms around it and have a clear sense of what’s causing it,” Friedman said. “Which would obviously help us in treating it and insuring that it didn’t re-occur.”

Friedman added, “Whenever we do figure out the primary culprit, I think it will then feel obvious. But in this moment, it doesn’t.”

Hill is not eligible to return until April 27, but manager Dave Roberts indicated Hill would be unlikely to come back after only 10 days. Hill will probably need to embark on a rehabilitation assignment, and could spend time in the bullpen upon his return.

Until then, Hill will continue to throw. The club does not want Hill’s arm to lose its stamina. He also needs to build a callus on his finger, which the throwing could help.

Hill signed a three-year, $48-million contract over the winter. Friedman was asked if the organization considered the possibility of the blister’s return as part of the risk inherent in signing Hill. “We felt confident that it was behind us, obviously didn’t know for sure,” Friedman said.

Friedman acknowledged that the team understood the possibility of Hill’s requiring time on the disabled list. At 37, Hill has thrown 618 1/3 innings in parts of 13 big league seasons. He has undergone an elbow reconstruction and a surgery on his labrum.

“What was baked into the contract was that we weren’t counting on 200 innings,” Friedman said. “You’re counting on more limited innings than you traditionally would [throw], but with really good quality, and hopefully trying to time it for October, if you qualify.”

Short hops

The roster continued to churn Tuesday as the team placed left-handed reliever Grant Dayton on the 10-day disabled list because of a left intercostal muscle strain. Dayton had thrown a scoreless inning in relief Monday and had not allowed a run in seven appearances. In his place, the team recalled right-handed reliever Josh Fields.

andy.mccullough@latimes.com

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