Pittsburgh Steelers rookie running back Le'Veon Bell is getting a second opinion on his mid-foot sprain and likely will miss Saturday's preseason game against the Kansas City Chiefs, coach Mike Tomlin said Wednesday.Fox Sports and NFL.com reported that Bell may have a Lisfranc injury, which could sideline him for eight to 10 weeks. The team is awaiting a diagnosis from the second evaluation.Bell underwent an MRI on Tuesday, but Tomlin said Wednesday morning that he did not know the severity of the injury. He was hurt during the first quarter of the Steelers' 24-13 loss to the Washington Redskins on Monday night.The second-round draft pick had missed Pittsburgh's preseason opener with soreness in his left knee. He made his NFL debut against the Redskins, rushing for 9 yards on four carries before the injury.Bell is listed as a co-starter on the team's depth chart at running back with Isaac Redman, who is battling a stinger. Running backs LaRod Stephens-Howling (knee) and Baron Batch (stinger) also are injured.Steelers tight end Matt Spaeth is projected to miss eight to 10 weeks with the Lisfranc injury.