BOARDMAN, Ohio No, Youngstown, Ohio, didn't experience a small earthquake about 2 p.m. Wednesday. It was just 49ers running back Brandon Jacobs returning to practice.
The 260-pound Jacobs joined teammates for warmups and individual drills for the first time since Aug. 18, when he was carted off the field in Houston after taking a helmet to his left knee. Jacobs officially was listed as limited on the team's injury report, but he appeared to be moving well during the portion of practice open to the media.
The 49ers are practicing this week at Youngstown State's Stambaugh Stadium.
Linebacker Patrick Willis also seemed unhampered after suffering an ankle injury late in Sunday's loss to Minnesota. He participated in a full practice.
Wide receiver Ted Ginn (ankle) went through individual drills with his teammates and was listed as limited.
The lone 49er who did not practice was nose tackle Isaac Sopoaga, who suffered a left knee injury in the fourth quarter Sunday. If Sopoaga can't play Sunday against the New York Jets, Ricky Jean Francois would step in at the position.
Practicing on a wet field, Jacobs and the running backs went through a rarely seen drill, one that used a football tethered to a long cord. The other end of the cord was attached to a fence, and the player with the ball ran in a semicircle with the cord applying tension to the ball.
The drill was meant to test ball security on a team that uncharacteristically gave up two fumbles one by Frank Gore and the other by Alex Smith in the loss to the Vikings.
If Jacobs is fully healthy Sunday, he likely would be worked into games as a short-yardage runner. Through three games, only two running backs Gore and Kendall Hunter have carried the ball for the 49ers. Gore has 45 carries for 264 yards, and Hunter has 18 carries for 64 yards.
As for the other running backs, Anthony Dixon has been a mainstay on special teams, and rookie LaMichael James has been inactive for every game so far this season.
Davis praised Jets coach Rex Ryan on Wednesday called Vernon Davis the best tight end in the league. Asked which of the 49ers' offensive players he had to be most wary of this Sunday, Ryan rattled off several names. But he began with Davis.
"The No. 1 tight end in football, in my opinion," Ryan said on a conference call. "You've got that (Rob) Gronkowski kid. But this guy (Davis) is a 4.3 speed guy."
Through three games, Davis is tied with Pittsburgh tight end Heath Miller for the league lead in touchdown catches with four.