PEORIA, Ariz. -- Padres left fielder Alex Dickerson was sent back to San Diego on Wednesday to have his ailing back checked by a spine specialist, manager Andy Green said at the team's complex Wednesday.
The ailment resurfaced after Dickerson worked out Sunday, and he was scratched from Monday's lineup against the Cubs, raising questions about his status for Opening Day.
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"Dickerson is seeing a spine specialist, who's going to look at his back more thoroughly and get an idea if there's anything that we need to do differently for him going forward," Green said. "He's a big part of what we do. He's a very professional hitter that we had the expectation was going to get middle-of-the-order-type at-bats for us this season, so that's a very important guy in the lineup."
Dickerson, who had a slash line of .257/.333/.455 in his 2016 rookie season, was expected to receive the bulk of the playing time in left field this season. He missed the first two weeks of Cactus League play because of the back ailment before debuting as a designated hitter Saturday.
Monday's game was supposed to be Dickerson's first appearance in the outfield. But his back began to stiffen following Sunday's workout.

"Right now, since there was a relapse with it, you get more concerned," Green said. "If it was just a one-time, isolated incident, you don't think much of it. But with the tightening up of his back prior to his next scheduled start a few days back, we just thought it best to get him really thoroughly examined and figure out if there's anything different we need to do."
Dickerson was called up for a stint in May, then called up to stay in late June. He slashed .303/.343/.621 in July, his first full month in the Majors, and was instrumental in the Padres' National League record-tying 25-game home run streak.
At the end of that month, however, Dickerson collided with center fielder Travis Jankowski, hurting his hip and back in the process. After missing a few games, he played through the injury but mostly struggled the rest of the season. It's unclear whether the current back injury is related.
Jankowski, Hunter Renfroe and Manuel Margot remain favorites to break camp with the big league club. That could leave Jabari Blash and Collin Cowgill fighting for Dickerson's presumed spot. Prospect Franchy Cordero may have an outside chance as well.
Catcher Hedges cleared to play

Green said Austin Hedges is healthy and has been cleared to start Friday against the Dodgers at Peoria Stadium in a 7:10 p.m. PT start.
Hedges came out of last Thursday's game after two innings with a sore left hamstring. He sustained the injury trying to leg out a grounder in the hole between short and third.
"Hedges went through the paces [Wednesday] and feels great," Green said. "He's going through the workout as well, BP, a full go. He'll be off [Thursday] from games, and then the expectation is he starts in Friday night's game."