Source: Niners WR Deebo Samuel (pneumonia) out of hospital

SANTA CLARA, Calif. -- San Francisco 49ers receiver Deebo Samuel is out of the hospital after being treated for pneumonia.

Samuel was released from a local hospital Tuesday afternoon, a team source told ESPN. He checked into the hospital Sunday night after it was discovered that he had fluid in his lungs.

"I think it started acting up in the middle of the night Saturday night or early Sunday morning and then it just kind of evolved as the day went," coach Kyle Shanahan said Monday. "Once we found out he had the fluid in his lungs and stuff after the game, then I believe they sent him over there."

Samuel first began feeling ill late Saturday into early Sunday. He arrived at Levi's Stadium and the team announced he was ill but expected to play about 30 minutes before kickoff against the Kansas City Chiefs.

But Samuel was only able to play four snaps before leaving the game. He did not return and Shanahan said later that Samuel was having trouble breathing in addition to throat and stomach issues.

Shanahan said Monday he wasn't sure if Samuel would be available for Sunday night's game against the Dallas Cowboys, though more clarity on that should come Wednesday when the Niners return to practice after being off Tuesday.

Samuel is one of multiple Niners receivers dealing with an illness or injury. Brandon Aiyuk's season is over because of a torn ACL and MCL in his right knee, Jauan Jennings has a hip injury and Chris Conley has a sprained ankle.