CHICAGO -- Injuries continued to gnaw at the Chicago Bears on Saturday when starting nickel corner Kelvin Hayden strained his left hamstring, and receiver Earl Bennett left practice with athletic trainers to be evaluated for a concussion.

The team said Hayden is week-to-week, while results for Bennett’s concussion evaluation weren’t made available.

Bennett suffered the injury during a collision with safety Chris Conte during team drills.

“No, I did not see [the collision],” Bears coach Marc Trestman said.

Bennett missed two games in 2012 after sustaining a concussion during a Week 12 loss to the Seattle Seahawks.

In other injury news, rookie defensive end Cornelius Washington suffered a strained elbow and is day-to-day. Receiver Alshon Jeffery and defensive end Julius Peppers both experienced hamstring tightness, forcing the staff to pull them out of practice as a precautionary measure. Neither is expected to be out for an extended period.

The team also held out offensive tackle Jermon Bushrod (calf), defensive end Jamaal Anderson (knee), linebacker D.J. Williams and offensive tackle Jonathan Scott (knee). Defensive end Corey Wootton (hip) suited up for Saturday’s practice, but only took part in individual drills before taking on a spectator’s role for full team work.

Wootton appeared to be hobbled during the limited time he worked.

“[I’m] feeling better. I did individual [drills] today. I just kind of tweaked it,” Wootton said. “I’m just trying to get back in the swing of things. There’s a little bit [of discomfort]. I’m just trying to work through it, be smart at the same time, and just come back when I’m healthy.”

Other notes:

Newly-signed tight end Leonard Pope took part in his first practice Saturday at Soldier Field when the club conducted its annual Family Fest.

Pope officially signed with the Bears on Saturday morning. An eight-year veteran, Pope started in 51 of 103 games with the Arizona Cardinals (2006-08), Kansas City Chiefs (2009-11) and the Pittsburgh Steelers (2012), catching 105 passes for 982 yards and 11 touchdowns.

“It’s a blessing. I’m just happy to be able to have the opportunity to be here and bring what I need to bring to the table; to just be able to help out whenever I’m able to help out,” Pope said.

Players were introduced and ran out onto the field for the start of practice, and when the announcer got to the defensive backs, he called their names one by one just like he had done with the coaches and every other position.

“Kelvin Hayden,” the announcer said. But no one came onto the field for several seconds. The announcer followed with “Sherrick McManis.”

Still, nobody emerged.

Several seconds later, all of the team’s defensive backs came out onto the field at the same time.

Throughout training camp, the team’s defensive backs have shown more unity than most of the position groups. The group put that on display just a day before, when Hayden became involved in a scuffle with tight end Martellus Bennett that eventually involved almost every member of the secondary.

Tight end Gabe Miller fooled safety Brandon Hardin on a double move during one-on-one drills for a reception.

During the same drill, tight end Fendi Onobun got separation on safety Craig Steltz but dropped what appeared to be a perfectly thrown ball.

Kick returner Devin Hester returned a kickoff during a special-teams drill, and tossed the ball into the crowd when he reached the end zone.

Trestman raved about his team’s energy level during Saturday’s night practice at Soldier Field.

“It was just exciting to be out here tonight,” he said. “You can see our players just had a blast out here. Our effort was at a high level. There was great competition. We have to remember that it was still just practice, and we were trying to improve as a football team. I’m sure coming out here tonight, being in this crowd, helped our energy level after seven practices.”