Brennen Davis — the top prospect in the Chicago Cubs organization — has back surgery

The back injury to Chicago Cubs top prospect Brennen Davis is more serious than initially thought.

Davis had back surgery in Los Angeles Thursday, sources told the Chicago Tribune. The 22-year-old outfielder went on the Triple-A Iowa injured list May 12 after he had been bothered by low back stiffness that traces back to spring training. The surgery revealed a cluster of blood vessels that caused back and leg pain. The vascular malformation pushed against a nerve, not dissimilar to sciatica.

The blood vessels were cauterized during the surgery, and Davis has a follow-up appointment with the surgeon next week. It’s a best-case scenario given the situation for Davis, who does not have any disc or structural issues in his back.

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He is expected to make a full recovery. However, there is no timetable for when Davis will return to baseball activities. It is too soon to say how much of his season will be impacted by the surgery.

The ailment initially manifested as a back injury, but the pain migrated to his legs. Davis received an epidural, which was expected to help resolve the issue. The pain, though, continued to worsen through his back and legs. Going into Thursday’s surgery, the thought was Davis had been dealing with a potential disc issue in his back.

Davis had a .195/.286/.299 slash line with two doubles and two home runs in 22 games at Triple A before landing on the injured list. Heading into the season, he was a candidate to join the Cubs at some point this season. That is now on pause as he works back from the surgery.