‘Big issues to solve’ as injuries hit O-line

The Raiders emerged from Sunday’s 24-21 win over the Steelers hobbled on their offensive line.

With Pro Bowl left guard Kelechi Osemele inactive because of a toe injury, Jon Feliciano started and suffered a calf injury late in the game. Head coach Jon Gruden said Monday: “There’s a good chance Feliciano might be gone for the season.”

Feliciano doubles as the Raiders’ backup center. In addition, right guard Gabe Jackson sustained an elbow injury of unknown severity, Gruden said, leaving the state of the interior line in doubt.

“We have big issues to solve,” Gruden said. “That’s a big concern.”

Despite the injuries, both Feliciano and Jackson played every snap of Sunday’s game, which the Raiders won on a touchdown pass from Derek Carr to Derek Carrier with 21 seconds left.

“You had to see a guy go out there and put himself at risk,” Gruden said. “But Feliciano, Gabe Jackson, they insisted on going out there and finishing that drive.” Lofty praise: Gruden said it should be a “high priority” this offseason for the Raiders to resign tight end Jared Cook, who will be a free agent after the season.

Cook had seven receptions for 116 yards Sunday and has set career highs for a season in catches (61), receiving yards (825) and touchdowns (six) with three games left to play. Cook is fourth among NFL tight ends in receiving yards and tied for third in touchdowns.

“Whoever the general manager is, we’ll show him some tape of Jared Cook,” Gruden said Monday, shortly after the Raiders announced they’d fired general manager Reggie McKenzie. “This guy’s been dazzling as a receiver. We’ve been able to put him in so many different positions, in the slot, at wide receiver. ... Really, really excited about the season he’s had.” Saying no: NFL Network, which first reported McKenzie’s departure Monday, also reported that a disconnect arose from Gruden running a separate personnel department from McKenzie with his own scouts and evaluation boards. Gruden was asked about the report Monday.

“I have a couple of guys that work for the coaches,” Gruden said. “We have different needs than the scouts. We’re not scouting players. We’re getting ready for an opponent. So yes, we do have people working for the coaches. But it doesn’t intersect with scouting at all. It’s a completely different agenda.” Matt Kawahara is a San Francisco Chronicle staff writer.