Manager Don Mattingly stopped short of ruling Ryu out of Wednesday's game, but also said Saturday's exam indicated soreness in the back of Ryu's shoulder. When Ryu missed three weeks earlier in the year, the Dodgers said Ryu had a tired and inflamed shoulder.

"Very doubtful," Mattingly said of Ryu making the start Wednesday.

In fact, the Dodgers don't know if they will have Ryu back at any point this year.

Frias has been pitching out of the bullpen since his callup from Triple-A, but he also made a spot start and pitched six scoreless innings against Washington on Sept. 3. Mattingly said his ground-ball-inducing sinker would be an asset for a start at Coors Field.