Dodgers' Tim Redding suffers injury

TUCSON, Ariz. -- On a day it became clear they will begin the season with four of their regular players on the disabled list -- catcher Dioner Navarro joining pitchers Vicente Padilla and Jon Garland and third baseman Casey Blake -- the Los Angeles Dodgers appear to have dodged another notable injury during the afternoon half of their split-squad, Cactus League doubleheader, a 6-3 loss to the Arizona Diamondbacks before a sellout crowd of 10,820 at Kino Sports Complex.

Tim Redding, a non-roster right-hander who was one of two competitors for the fifth spot in the rotation in the likelihood Garland won't be ready to return when the Dodgers need a fifth starter for the first time on April 12, left the game in the fourth inning Friday because of pain on the right side of his lower back.

Redding returned to Camelback Ranch, the team's spring-training complex in Glendale, for further examination. He was diagnosed with nothing more serious than a sore back and is listed as day to day for now.

The Dodgers also lost the nightcap, 6-0 to a Seattle Mariners split squad before 7,689 at Peoria Sports Complex.

Redding and John Ely are battling it out for the fifth spot, but manager Don Mattingly indicated before the game that neither will be on the opening day roster as a reliever; instead, they will be called up from the minors if needed.

Mattingly also sounded at least somewhat resigned to Garland missing more time than that.

"It's up in the air, but we know it's going to be close," Mattingly said. "I'm sure he wants to be ready, and we would like for him to be ready. But I'm going with what [trainer] Stan [Conte] said, that we aren't going to put him out there until he is ready. With [Garland], I want the whole picture, not just that first snapshot."

The season opener for Triple-A Albuquerque isn't until April 7, so whomever the Dodgers choose to start in place of Garland could start that game and then be perfectly lined up to pitch for the Dodgers on April 12 in San Francisco.

Ely and Redding each started one of the Dodgers' games Friday. Mattingly said Ely and top pitching prospect Rubby De La Rosa, who definitely will start the season in the minors, will pitch in the team's spring finale Wednesday night against the Seattle Mariners at Dodger Stadium. Redding was scheduled to make his final spring start that day in extended spring training at Camelback Ranch, but it isn't clear now whether he will be able to do so.

Short hops

Barring an injury, infielder Ivan DeJesus looks like a strong bet to make the club and remain in the big leagues until Blake returns from a back injury. DeJesus, who will be making his major league debut, likely will get the bulk of the starts at second base during that time, while Juan Uribe will move to third. ... Infielder Jamey Carroll has played seven innings at shortstop each of the past two days after not playing in the field at all for several days because of lingering soreness in his right index finger. Carroll said his throws across the diamond still don't have a lot of velocity on them, but that is gradually improving and he isn't concerned. ... The Dodgers play the San Diego Padres at Peoria Sports Complex on Saturday. Clayton Kershaw will pitch for the Dodgers against Dustin Moseley, marking Kershaw's final start before getting the ball for the season opener Thursday night against the San Francisco Giants and two-time Cy Young Award winner Tim Lincecum.

Tony Jackson covers the Dodgers for ESPNLosAngeles.com. Follow him on Twitter.