Sano, ranked as the No. 4 overall prospect by MLB.com, is likely to miss the rest of the season. The timetable for position players having Tommy John surgery is generally eight months rather than the typical 12-month recovery for pitchers.
"We believe the right thing is to go ahead with the surgery," assistant general manager Rob Antony said. "I still need to confer with his agent to get all the logistics regarding that, but basically from everything I've gathered from our doctors and trainers, it's an eight-month process from start to finish.
"[Sano will] hopefully be doing some hitting things four months after the surgery. We hope to have the surgery sometime within the next month. He'll have plenty of time to get ready for next year's Spring Training."
Sano, 20, is scheduled to fly back to the Twin Cities and to have the surgery next week, but the Twins haven't announced which doctor will perform the operation.
"I feel bad for the kid. But the amazing thing about him is, he's so upbeat," Twins manager Ron Gardenhire said. "It's sad. He wants to play baseball. We were all looking forward to him having a good year. But the key here is getting him healthy. He needs to be healthy, so get this thing fixed -- whatever they're going to do -- and go from there."
Sano, who had a chance to make his big league debut this year, was disappointed about missing the season but was confident that the injury would not hamper his career.
"When I come back, I'm the same player," Sano said.
Sano was originally diagnosed with a strained UCL this offseason after playing in just two games in his native Dominican Republic in the Dominican Winter League. But after consulting with Twins doctors and Dr. James Andrews, it was determined Sano needed only rest and rehabilitation instead of surgery.
Antony explained that if Sano had the surgery in November, he would've missed most of the Minor League season, so the Twins were hoping Sano would be able to play the whole season after rehabbing this offseason. Antony added that Sano didn't reinjure his elbow, as the MRI results were the same as they were in November. The elbow just didn't get any better.
"[Sano] might've been ready at the tail end of the regular season [if he had surgery in November]. But if you can avoid surgery, [you try] any time you have that chance, [and] he might not have missed any of the season," Antony said. "So do you want to be back for the last month of the season or possibly play the entire season? It was our doctors and Dr. Andrews who agreed that it was the right course of action. So we don't have any regrets on how it was handled."
Sano, who hit a combined .280/.382/.610 with 35 homers, 30 doubles and 103 RBIs in 123 games split between advanced Class A Fort Myers and Double-A New Britain last season, was cleared to throw at the start of Spring Training, and he didn't have any issues until Thursday's intrasquad game.
The Twins were hopeful that it was just normal soreness or inflammation, but the MRI exam on Friday confirmed their worst fear that the infielder would need season-ending surgery.
"It's disappointing for the organization, but more disappointing for the player," Antony said. "He's a 20 year old who is arguably one of the top five prospects in the game. Everybody has to deal with adversity in their career, so this is a slight setback for him. But hopefully he can get this taken care of and come back strong, and he'll be back in big league camp next year at 21."