ORCHARD PARK, N.Y. -- Buffalo Bills starting receiver Jordan Matthews and starting linebacker Ramon Humber are out indefinitely because of broken thumbs for a team already lacking experienced depth.
Coach Sean McDermott says the two will require surgery after both were hurt in a 23-17 win at Atlanta on Sunday.
Buffalo's receiver depth was already thin after Sammy Watkins was traded to the Los Angeles Rams in August, and Anquan Boldin retired two weeks after signing with the team in training camp.
Matthews was acquired in a trade with Philadelphia in August. The fourth-year player leads Bills receivers with 10 catches for 162 yards, and scored his first touchdown of the season Sunday.
One option at receiver won't be Walt Powell. Buffalo released the player on Monday, when Powell was eligible to return after serving a four-game NFL suspension for violating the league's policy on performance enhancing substances.
Humber entered Week 4 with a team-leading 29 tackles, and also had an interception while starting at outside linebacker.
McDermott says backup safety Colt Anderson will also require surgery for an injury to his forearm.
The injuries tempered the growing buzz Buffalo (3-1) has generated in getting off to a better than expected start, which has the Bills leading the AFC East.
Buffalo plays at Cincinnati (1-3) on Sunday before entering its bye week.
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