49ers' Ricky Pearsall shot in 'attempted robbery' in San Francisco: Police

San Francisco 49ers rookie Ricky Pearsall was shot during an "attempted robbery" in San Francisco's Union Square, according to police.

The 23-year-old "sustained a bullet wound to his chest and is in serious but stable condition," the San Francisco 49ers said in a statement.

Shortly before 4 p.m. local time, police responded to a report of a shooting and found two men "suffering from injuries," San Francisco Police Department said in a statement.

"During the attempted robbery, a physical altercation ensued, and both the suspect and victim were injured," according to SFPD.

Preliminary information indicates the wide receiver was targeted for a Rolex watch he was wearing, sources confirmed to ABC News.

Pearsall was walking along a street when a 17-year-old suspect from Tracy, California, approached and tried to rob him, police said during a briefing outside of San Francisco General Hospital.

Police said Pearsall was not targeted because he is a football player, it was a random street robbery.

The suspect is in custody and charges are pending at this time, police said in a statement.

San Francisco Police Chief William Scott told a press conference that the investigation into the incident was still active.

"This kind of violence is simply unacceptable in our city, and we will do everything in our power to work with District Attorney Brooke Jenkins to assure that justice is served in this matter," he said.

Asked whether the suspect had accomplices, Scott replied: "Right now, we believe it was one lone person. That may change as we get video evidence."

Jenkins told the press conference that she expected to make a charging decision "by the middle of next week, either Tuesday or Wednesday." Any charges will be filed in a juvenile court given the suspect's age, Jenkins added.

San Francisco Mayor London Breed, meanwhile, described the incident as "terrible and rare."

Pearsall -- a first-round draft pick -- had been dealing with a shoulder injury during the preseason and returned to practice last week, according to the National Football League.

ABC News' Erica Morris contributed to this report.