SANTA CLARA — Defensive end Nick Bosa, three weeks since straining his left calf, remains out of practice and could miss his fourth straight game Monday when the 49ers host Washington.

Bosa hoped to return this week and, in talking last Friday to reporters, said he otherwise for sure would be back for the Oct. 25 game at Atlanta.

“Nick is making really good progress. We’re encouraged by that,” general manager John Lynch said Friday morning on KNBR 680-AM. “… We want to make sure when we get him back, we have him back for good, that he’s not going to re-injure it. There’s no assurances there, there’s no absolutes, but we’ll continue to communicate with everybody involved, see if he can get out here (Friday). The extra day helps us, and so kind of a fluid situation there.”

Fluid, indeed, when it comes to their defensive line, which did produce a season-high five sacks in Sunday’s 32-29 win at Seattle.

Romello Height, who’s started the past two games opposite of Keion White, left the field Friday after a walk-through session and did not participate in the ensuing practice because of an illness.

Flu-like symptoms hit other teammates’ near his locker over the past two weeks, including kicker Eddy Piñeiro, tight end George Kittle and right tackle Colton McKivitz. Kittle said it took until Friday for him to fully recover after getting ill last Saturday.

Defensive tackle Greyson Halton (quadriceps) did not practice a second straight day but worked in pads on the side. James Thompson Jr. participated for the first time since a high-ankle sprain Sept. 20.

HEALTH CENTER

Wide receiver Mike Evans (ribs, Achilles) did some light work on the side but missed his second straight practice. He doesn’t look particularly hindered and is expected to play Monday, although his official status won’t be revealed until Saturday.

Wide receiver Christian Kirk practiced a second straight day as a short-term Injured Reserve candidate.

The Commanders listed 22 players on their injury report, and among those not practicing were linebacker K’Lavon Chaisson (knee; rest), running back Jacory Crosky-Merritt (groin), defensive tackle Javon Kinlaw (ankle, knee), wide receiver Terry McLaurin (hamstring; rest) and defensive end Charles Omenihu (groin, ankle).

TRADE CHATTER?

As the countdown begins toward the Nov. 10 trade deadline, general manager John Lynch confirmed calls are being made and received to “see where the market is at,” he said on KNBR 680-AM. Asked if Khalil Mack could be had from the Chargers, Lynch didn’t wade into those tampering waters but did not “a lot of people ask me that. … It’s usually Kittle because he asks about everything, which I love.”

Kittle said of his motives: “Anytime I see John Lynch on his little deck up there on the phone or texting, especially with us a couple weeks out of the trade deadline,
I just like to chirp and ask what he’s interested in, see if he’ll give me anything. … We ride who we came here with, and then if they want to add somebody, we will welcome them with open arms.’