ORCHARD PARK, N.Y. — The Buffalo Bills' passing game has had enough difficulty through the first month of the season.

The challenge may grow for the NFL's 31st-ranked passing offence.

The Bills (3-1) will be without top receiver Jordan Matthews for several weeks because of a broken right thumb. That places more pressure on an unheralded group of receivers that has already dealt with adversity this season.

"It is never easy to lose a player, any player, but also a player of that quality and calibre with Jordan Matthews," Bills coach Sean McDermott said. "We are not limited. We move forward and that is what good teams do."

The Bills have been one of the league's biggest surprises through four weeks, moving to the top of the AFC East following an upset win at the Atlanta Falcons. They'll be tested, though, after yet another setback at a critical position.

Matthews' injury is just the latest blow for Buffalo at wide receiver. The Bills sent their top wideout from the previous three seasons, Sammy Watkins, to the Los Angeles Rams in a preseason trade.

Veteran Anquan Boldin, who was originally expected to line up alongside Watkins — and then replace him — abruptly retired 10 days later.

Their No. 2 and No. 3 receivers from last season, Robert Woods and Marquise Goodwin, left in free agency. One year earlier, Chris Hogan left as a restricted free agent.

That leaves an untested group that includes second-round pick Zay Jones, veteran Andre Holmes and the returning Philly Brown to try and pick up the pieces.

"I don't think you can quite replace a player like Jordan, especially what he brings to the table as a football player," Jones said. "But it doesn't stop us. We've just got to keep preparing the same way."

Jones has the highest ceiling, but has had a rocky start to his pro career. Known for his hands and consistency at East Carolina, the 37th overall pick in the draft has struggled with drops.

Against Atlanta in Week 4, Jones had a poor drop before coming back with a tough catch by the sideline in the third quarter.

"I'm growing and I'm learning and I know that," Jones said. "I've had a lot of advice, a lot of people talk to me. I've heard a lot of things positive and negative, but I just really don't care because it's a learning process for me.

"This is fun. And I'm enjoying it still. There's been a lot of outside noise and a lot of outside talk but I'm still enjoying it."

Holmes, 29, is the veteran of the group. He spent the past four seasons as a depth receiver with the Oakland Raiders.

Brown was re-signed Tuesday after being released by Buffalo before the start of the season. Buffalo also has receivers Brandon Tate and Kaelin Clay, who have played mostly on special teams.

Working in Buffalo's favour is an offensive approach that has utilized its share of play action. Those adjustments have allowed quarterback Tyrod Taylor to use his mobility while simplifying reads and helping to create separation downfield.

"That has been huge," McDermott said. "With my defensive background, I know how tough that is in order to diagnose the run and then the play action that comes off of it. That is tough to handle defensively."

The Bills also have an option in tight end Charles Clay, who leads the team in receiving yards through four weeks (227 yards, two touchdowns). Clay had a big performance in the win over the Falcons with 112 of the team's 182 receiving yards.

After two seasons of solid but inconsistent production, the Bills have emphasized Clay in the passing game with their other options limited.

"We've tried to over the past couple of years," Taylor said. "We've been on the same page and he's gone out there and played at a high level."

Buffalo's receiving options will be put to the test on Sunday at Cincinnati (1-3), where the Bills have a chance to go to 4-1 for the first time since 2011.

"I have to go out there and make plays with whoever's out there and I have confidence in those guys in the receiver room, guys that are willing to step up and take the challenge," Taylor said.

"Yes, we miss Jordan but it's not going to be the end of the world either. He'll be back and we'll be better as a unit when he comes back."

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