Cubs top prospect Brennen Davis undergoes back surgery

Davis, 22, reportedly dealt with lower-back stiffness as far back as spring training. He eventually began to feel back pain that spread to his legs, leading to the surgery. 

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

While Davis could return to the field this season, there is no timetable for his return. It's a blow for the top prospect who was believed to be a candidate for a call-up to the big leagues this season. 

The Cubs selected Davis in the second round of the 2018 MLB draft out of Basha High School in Gilbert, Arizona. 

This season at Triple-A Iowa, Davis batted .195/.286/.299 with two home runs and seven RBI in 22 games. 

MLB.com has Davis listed as the 16th-best prospect in baseball.