SANTA CLARA -- Running back Carlos Hyde, who suffered a second-quarter concussion Friday, worked out on a side field Tuesday, signaling he is close to returning to practice.
Under the league's concussion program, Hyde's workout falls under the category of non-football activities. If he wakes up Wednesday asymptomatic, he can resume football activities -- likely practicing a blue jersey that identifies him as someone who cannot be hit -- on Wednesday.
The 49ers will have a walk-through practice Wednesday before Thursday's preseason finale in San Diego. Hyde was checked for a concussion in Week 2 last year in Pittsburgh but it was determined he did not suffer one.
Hyde is very unlikely to play Thursday. His top backup, Shaun Draughn, also may not play after taking a hit to the ribs Aug. 18 during a scrimmage with the Broncos. Draughn missed the next two preseason games because of the injury.
The top competition at that spot is between DuJuan Harris and Mike Davis for the No. 3 role. Rookie Kelvin Taylor also is available to play in the game.
With offensive tackle Erik Pears no longer on the roster, Colin Kelly and Fahn Cooper have been playing behind Joe Staley at left tackle. Cooper, a fifth-round pick, also can play guard. Another rookie tackle, John Theus, mostly has been on the right side. Theus has not practiced in full this week and was in a blue, no-contact jersey Tuesday.
Receiver Bryce Treggs and linebacker Nick Bellore were running today on a side field. Both are returning from knee injuries suffered against the Broncos Aug. 20. Another receiver, Bruce Ellington, was placed on injured reserve Tuesday, ending his season. Another, DeAndre Smelter, has been dealing with a persistent hamstring injury since the spring. Smelter was back at practice this week but not at full speed.
Chip Kelly said starting defensive lineman Quinton Dial (MCL) would not play Thursday against the Chargers but should be ready for the Sept. 12 opener against the Rams. Glenn Dorsey (ACL) has been taking part in defensive line drills all summer. It's not known whether he's been folded into any seven-on-seven or team drills at this point. He is unlikely to play in Week 1.