Gannon, a four-time Pro Bowler and last season's league MVP, was
pounded by the Kansas City defense throughout the first half of the
Raiders' 17-10 loss to the Chiefs on Monday night.
He was held out of the second half with a bruised right
shoulder. Seldom-used backup Marques Tuiasosopo led Oakland on a
fourth-quarter rally, nearly tying the game in the final seconds.
Callahan praised both Gannon and Tuiasosopo on Tuesday, but said
he isn't sure who will be the Raiders' first-stringer when the team
returns from its bye week. The Raiders are expected to find out the
severity of Gannon's injury on Wednesday.
"I'm not going to make any determination on the quarterback's
play until I know about his health situation," Callahan said of
Gannon. "This is the league's MVP. I have great respect for him
and everything he has done for the team."
After he was sacked by linebacker Shawn Barber on the final play
of the first half, Gannon went to the sideline holding his arm.
Gannon, 10-of-19 for 58 yards and an interception, received
treatment on the sideline while Tuiasosopo played the second half.
"When I tried to throw, I couldn't," Gannon said Monday night.
Tuiasosopo, who had just 69 yards passing
in his career before Monday night, rallied the Raiders to three lengthy drives and 10 points in the fourth quarter. But the comeback attempt ended when
two Chiefs tackled Tim Brown at the Kansas City 1 as time expired.
Earlier in the season, Callahan dismissed any notion of
occasionally using Tuiasosopo to keep Gannon fresh. But when asked
directly Tuesday whether Gannon's job was safe if the MVP's health
was sound, Callahan said: "I'm not going to make that decision or
even speculate or go there at this point."
Oakland's players had the day off Tuesday.
While leading the Raiders to three straight AFC West titles,
Gannon has been the focal point on one of the league's most
consistently excellent offenses. Last season, he led the NFL with
4,689 yards passing while setting league records with 418
completions and 10 300-yard passing games.
But the 37-year-old quarterback has been mostly terrible this
season along with his teammates as Oakland stumbled to a 2-5 start.
With a dismal passer rating of 73.5, Gannon has thrown for just
1,274 yards with six touchdowns and four interceptions.