According to the San Diego Union-Tribune, Maybin will undergo an MRI on Monday to determine the extent of the injury.
The Padres scored a run in the sixth off Stephen Fife. Jace Peterson walked, took second on a groundout, took third on Fife's wild pickoff throw and scored on Alexi Amarista's RBI infield single.
San Diego tied it in the eighth on an RBI single by Rocky Gale. Gale's hit drove in Rico Noel, who plated Jace Peterson with an RBI double.
Beckett, continuing his recovery from surgery for thoracic outlet syndrome, struck out three and allowed one hit, calling the outing a significant hurdle in his return from the injury.
Maholm, who was slowed this spring with elbow tenderness, also allowed only one hit.
The Dodgers scored in the second inning off San Diego starter Robbie Erlin, cashing in a walk to Joc Pederson with a single by Tim Federowicz and a fielder's choice grounder by Alex Guerrero.
They added to the lead in the fifth on singles by Guerrero and Justin Turner and a sacrifice fly by Yasiel Puig.
Up next: Josh Johnson will make his anticipated Padres debut Monday when the club travels to Scottsdale, Ariz., to face the Giants at 12:05 p.m. PT in an exclusive audio webcast on MLB.com. Signed to a one-year, $8 million deal in the offseason, Johnson is expected to begin the season in the middle of the rotation. The 30-year-old is coming off an injury-shortened 2013 season in which he only made 16 starts and finished with a 6.20 ERA for the Blue Jays.
Ken Gurnick is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.