EL SEGUNDO — Just when it seemed the Chargers offense might finally be ready for takeoff, the team announced four potential targets for quarterback Justin Herbert were listed Saturday as questionable to play Monday night against the Arizona Cardinals, and two others were said to be doubtful.

Wide receivers DJ Chark (groin), Derius Davis (hamstring), Simi Fehoko (shoulder/groin) and Ladd McConkey (hip) were listed as questionable to play. Chark, Davis and McConkey were said to be limited participants in Saturday’s practice. Fehoko was a full participant.

Tight end Hayden Hurst (groin) and wide receiver Quentin Johnston (ankle) were listed as doubtful to play against the Cardinals. Hurst and Johnston did not participate in Saturday’s practice. Tight end Will Dissly, who began the week with a shoulder injury, was a full participant and is expected to play.

All of which begs the question: Who will Herbert throw the ball to today?

The string of injuries happened just as Herbert’s sprained right ankle is trending in the right direction. His mobility and accuracy were on display during the Chargers’ victory this past Sunday over the Denver Broncos, when he set season highs for completions with 21, attempts with 34 and yards with 237.

It’s possible Herbert will be without his top two targets in McConkey and Johnston. McConkey, a rookie Herbert referred to as a quarterback’s best friend because of his precise routes and sticky fingers, has a team-leading 19 receptions for 219 yards. Johnston leads the Chargers with three touchdowns.

McConkey and Johnston were injured during the Chargers’ 23-16 victory over the Broncos. McConkey caught four passes for 43 yards and Johnston caught three passes for 22 yards against Denver. Dissly also caught four passes against the Broncos, stepping up after Hurst was hurt.

If there was a ray of sunshine in Saturday’s otherwise bleak report, it was that Chark might be set to make his season debut after sitting out the season’s first five games because of injuries. The Chargers on Monday opened his 21-day window to return to practice from injured reserve.

Chargers coach Jim Harbaugh answered a question about an experienced player like Chark, who is in his seventh season in the NFL, adding depth to a battered and bruised wide receiver corps by speaking about the advancements made by Joshua Palmer as the season progresses.

“I would just say we like our receiver room a lot,” Harbaugh said. “I don’t have that list (of attributes) in front of me. (But) DJ is a really good player. We’ll be excited when he’s back. We’re excited about Josh Palmer and where he’s at, what he’s been doing. Big third-down conversions last week (against Denver).

“I think he’s heating up.”

Palmer has nine catches for 108 yards this season. He had two catches for 38 yards against the Broncos, both for third-down conversions in the first quarter. One extended a drive that led to Herbert’s 38-yard touchdown pass to Kimani Vidal. The other continued a 20-play drive that set up a field goal.

WHAT ABOUT BOSA?

The Chargers listed outside linebacker Joey Bosa as doubtful to play today because of injuries that have limited him to three games this season. His latest ailment was a hip injury that he suffered on the opening play of the Chargers’ loss to Pittsburgh in Week 3.

“Working through something,” Harbaugh said. “Encouraged by the progress.”