League, 32, had issues with his shoulder from the earliest days of spring training, and his minor league rehabilitation assignment was coming to a close, with the 30-day limit arriving Tuesday.
Two days earlier, Dodgers manager Don Mattingly said the team had been debating whether League was among the seven most effective relief pitchers at the team's disposal. Apparently, the response came back in the negative.
The Dodgers will have to pay League what remains of his $7.5 million salary.
League worked hard to return after admitting at one point he considered whether his career might be over when doctors reviewed the MRI on his right shoulder. It had bothered him all spring. League pitched 10⅔ minor league innings of rehab and allowed just one run, although the 94 mph sinking fastball he used to throw was nowhere to be found. League, according to scouts, struggled to touch 90 mph.
League pitched two strong months for the Dodgers after they acquired him near the trade deadline in 2012, then signed a three-year, $22.5 million extension offered by then-general manager Ned Colletti. League struggled after the deal, ceding closing duties to Kenley Jansen early in the contract, but he had a bounce-back season as a middle reliever in 2014, posting a 2.57 ERA.