Allen injured his knee during an ill-fated onside kick attempt in Cal's 49-27 loss to Utah last week. In addition to being the Bears leading receiver, Allen is also one of the top receivers in the Pac-12. He racked up 1,343 receiving yards last season and is seventh in the Pac-12 in receiving yards per game this season.
Without Allen, Cal will be forced to rely on a pair of freshman at wide receiver. Freshman Chris Harper is California's second-leading receiver this season with 380 yards. Bryce Treggs, another freshman, is Cal's third-leading receiver although he is questionable to play on Friday due to an ankle injury.
Playing without Allen, Cal may look to run the ball more against Washington. The Bears are averaging 169.0 rushing yards per game this season, which is fifth best in the Pac-12.