The San Francisco Chronicle's Susan Slusser reported Pinder was involved in a car accident in Denver on Saturday and suffered a gruesome arm injury:
Pinder is averaging .259 with 10 home runs and 23 RBI through 71 games for the Athletics. His 1.4 WAR is sixth among Oakland position players, per FanGraphs.
Although it's unclear when Pinder might be able to return to the field, Slusser's report he "won't be allowed to swing for awhile" likely means he could be out for an extended period of time.
The A's recalled Franklin Barreto to take Pinder's spot on the 25-man roster. Khris Davis, meanwhile, will continue to fill in for Pinder in left field. Davis, who has spent much of the season as the designated hitter, started in left for each of Oakland's last three games.
The Athletics have been one of the biggest surprises in MLB and sit one game back of the Seattle Mariners for the final wild-card spot in the American League. Losing Pinder isn't a critical blow to Oakland's playoff hopes, but it's unquestionably a setback for the team in its quest to return to the postseason for the first time since 2014.