ALAMEDA, Calif. (AP) - Oakland Raiders first-round draft pick D.J. Hayden's comeback from a near-fatal practice injury last year was dealt a setback when he was hospitalized with an abdominal injury that is expected to keep him sidelined until at least training camp.

Coach Dennis Allen said Tuesday at the start of Oakland's second week of OTAs that Hayden first felt symptoms last Tuesday or Wednesday. The cornerback was hospitalized late last week and had surgery to remove scar tissue from the abdominal region. The Raiders said they don't know when Hayden will be released from the hospital.

Allen said he did not know if the latest injury was related to the torn blood vessel that nearly killed Hayden last November after a practice collision with a teammate at Houston.

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