On offense, the Bills haven't turned over the ball since Tyrod Taylor threw an interception on the first drive of a season-opening 21-12 win over the New York Jets. They're also getting clutch production from kicker Stephen Hauschka, who has hit eight of nine field-goal attempts, including all four from beyond 50 yards.
All the first-year coach could focus on were the pitfalls that lay ahead with Buffalo preparing to play at Cincinnati (1-3) on Sunday.
That leaves Buffalo leaning further on second-round pick Zay Jones and third-stringer Andre Holmes, who have combined for 10 catches and 92 yards, plus Holmes' two touchdowns.
"It's a different team," said McDermott, who took over after Rex Ryan was fired in the final week of last season.
Matthews, acquired in a trade with Philadelphia, leads Bills receivers with 10 catches for 162 yards, and scored his first touchdown of the season Sunday.
Matthews' injury leaves Buffalo without its most proven threat after Sammy Watkins was traded to the Los Angeles Rams in August, and Anquan Boldin abruptly retired two weeks after signing with the team in training camp.
Injuries are starting to become a factor in thinning a roster that began the season already lacking experienced depth.
"We're not where we need to be. And anyone who thinks we are, in this building at least, is only fooling themsleves," McDermott said Monday. "I'd like to believe that I'm honest with myself when I look at our football team. And I see a team that has to continue to improve."
McDermott provided no apology for being a buzzkill a day after a rousing 23-17 win at Atlanta vaulted the Bills (3-1) atop the AFC East standings — the latest in the season they've led the division since Week 7 of 2008.
"That said, we can learn a lot of lessons from those guys that were here when they went through that," he added. "Things happen in a hurry in this league. And we've got to stay hungry. We've got to stay humble."
Buffalo's defense has been stingy and opportunistic, while its offense has been modestly efficient.
NOTES: The Bills had 10 defenders on the field when Ryan threw an incompletion on fourth-and-1 from Buffalo's 10 to end the Falcons' final drive in the final minute. Linebacker Lorenzo Alexander was the missing player, defensive coordinator Leslie Frazier said. ... McDermott said backup safety Colt Anderson will require surgery for an injury to his forearm. ... WR Walt Powell was released upon being eligible to return after serving a four-game NFL suspension for violating the league's policy on performance enhancers.
The recent past also presents a cautionary tale,Wholesale NFL Jerseys.
ORCHARD PARK, N.Y. (AP) — Bills coach Sean McDermott would like everyone to tap the brakes before getting overly excited about the team's better-than-expected start to the season.

This marks just the third time since Buffalo's playoff drought began that the team has gotten off to a 3-1 start or better. The Bills were 3-1 in 2011 before finishing 6-10. In 2008, Buffalo won its first four games before losing nine of its last 12.
Starting receiver Jordan Matthews and starting outside linebacker Ramon Humber are out indefinitely, both requiring surgery after breaking a thumb against Atlanta.
If the growing number of injuries to key players isn't enough to give the first-year coach reason for pause,Cheap Authentic NFL Jerseys, the Bills' history of mid- to late-season collapses during their 17-season playoff drought also serves as a sobering reminder.
Humber entered Week 4 with a team-leading 29 tackles, and also had an interception. Two of Buffalo's three backup linebackers are rookies,Wholesale Jerseys Online, while Deon Lacey is playing his first NFL season after spending the past three in the Canadian Football League.
The Bills have allowed four touchdowns, matching the third fewest through the first four games in team history. Against Atlanta, the Bills forced three turnovers,Cheap Soccer Jerseys, including rookie cornerback Tre'Davious White returning Matt Ryan's fumble for a touchdown.
"We're certainly facing adversity,Wholesale NBA Jerseys, and we've faced adversity before," McDermott said. "And this is only going to make us stronger."