Mattingly discusses Dodgers' key injuries

CINCINNATI -- Left-hander Hyun-Jin Ryu, scratched from his scheduled start on Friday due to back stiffness, said he is optimistic about being ready to return on Wednesday against Arizona.

"I was never worried in any way," said Ryu through an interpreter. "I'm feeling a lot better, but [starting Wednesday] is up to the manager."

Manager Don Mattingly said he is "fairly confident" Ryu will be available.

Mattingly also said left-hander Chris Capuano, who had to come out of his start on Friday with a mild groin strain, will need to throw a bullpen session before his status becomes clear.

"He was smart enough to stop," Mattingly said. "Hopefully, this is not something that is major or long term."

The Dodgers do have options for their rotation, however. The addition of Edinson Volquez gives them six pitchers capable of starting.

Injured outfielder Matt Kemp (hamstring), who was shut down on Friday, took 15 simulated at-bats but did not run during his rehab work on Saturday in Arizona. Mattingly said Saturday and Sunday would be "fairly important days" to determine whether Kemp will be able to rejoin the club before the season ends.