Week 18 of the NFL season comes shrouded in mystery when it comes to player availability — especially when the game has no postseason implications. That will be the case this Sunday when the Kansas City Chiefs travel to the West Coast to play their final game of the regular season against the Los Angeles Chargers.

We know that quarterback Blaine Gabbert will start the game, but that’s about it in terms of offensive playing time. Many have suggested tight end Travis Kelce may appear in the game briefly to get to his eighth straight season of 1,000 yards (the magic number is now 16), but he was listed as a limited participant on Wednesday’s injury report with a neck issue.

Gabbert did note to expect more playing time than usual for Justyn Ross, Mecole Hardman and Kadarius Toney — but Toney (hip) couldn’t practice Thursday after a limited session on Wednesday. Left tackle Donovan Smith’s status is also up in the air. He did not practice Thursday after a full session on Wednesday. Smith has been dealing with a stinger for the past couple of weeks.

Running back Isiah Pacheco (groin) did return to practice Thursday after having to sit out on Wednesday — but presumably, the Chiefs will be cautious with him. Wide receiver Rashee Rice is also unlikely to play due to missing two straight days of practice thanks to a hamstring injury.

On the defensive side, coordinator Steve Spagnuolo was forthcoming in saying that he would be looking at plenty of backups on Sunday. He specifically named rookie defensive end Felix Anudike-Uzomah, safety Deon Bush, linebacker Leo Chenal, linebacker Jack Cochrane, defensive end Malik Herring, rookie linebacker Cam Jones, defensive tackle Derrick Nnadi, rookie defensive end B.J. Thompson and defensive tackle Turk Wharton as players he is eager to watch.

It’s doubtful that cornerback L’Jarius Sneed will play — he continues to rest his calf injury — and defensive tackle Chris Jones (groin) is also up in the air. Both players missed practice Wednesday and Thursday — but there is the matter of the half-sack that Jones needs to reach a $1.25 million incentive bonus.

Perhaps that will leave the door open for him to play.

“I would love for Chris to get that,” said Spagnuolo. “I think that’s always good. We don’t let get that in the way of what we’re trying to do. That means preventing points and [winning] football games.”

Spagnuolo’s words are encouraging — but as he would admit a moment later, the decision on Jones is not up to him.

“That’s the boss (head coach Andy Reid) who will make that decision.”