Identifying the biggest strength for the Buffalo Bills is a rather easy task. While they do have several star players on offense, including reigning NFL rushing champ James Cook, 2024 NFL MVP Josh Allen remains the key to their success.Buffalo tried to put more talent around Allen this offseason, as they traded for wide receiver DJ Moore. Critics say the Bills overpaid for Moore, but giving Allen a veteran wideout was an absolute must. If Buffalo is able to prove critics wrong and Moore does help Allen take his game to the next level, their offense could be among the best in the league.Even if the addition of Moore doesn't live up to Buffalo's expectations, Allen has enough talent to keep Buffalo competitive. That's why Kristopher Knox of Bleacher Report named Allen the team's biggest strength. As for the biggest weakness, that's where things get concerning.Buffalo Bills' biggest weakness could be their downfallAtlanta Falcons running back Bijan Robinson is tackled by Buffalo Bills defensive tackle Deone Walker. | IMAGN IMAGES via Reuters ConnectKnox says the Bills' biggest weakness is their run defense, which finished near the bottom in yardage surrendered as well as yards per rushing attempt this past season.“While the Bills have some talented pieces in their front seven, including defensive tackle Ed Oliver and linebacker Terrel Bernard, the group's inability to stop the run has been a massive defensive liability. Buffalo ranked 28th in rushing yards allowed and 30th in yards per carry allowed last season,” Knox wrote.“The Bills did little to address the issue in the offseason before using fourth- and fifth-round picks on linebacker Kaleb Elarms-Orr and defensive lineman Zane Durant, respectively. Longtime starting linebacker Matt Milano remains unsigned.”One thing Knox says that stands out is his claim that Buffalo didn't do much at all to address this weakness. He's spot-on, saying they waited until Day 3 of the NFL draft to add any defenders capable of shutting down the run. Buffalo did bring in multiple defenders during free agency, including safeties C.J. Gardner Johnson and Geno Stone, as well as outside linebacker Bradley Chubb. That said, they didn't sign any run-stuffing defensive tackles. Instead, they seem content to go into the season hoping that second-year player Deone Walker develops into a solid nose tackle in Jim Leonhard's scheme. They're also banking on players such as DeWayne Carter and Landon Jackson, who both bulked up during the offseason, to play more prominent roles in 2026.Shutting down the ground game will be key to the team's success, or lack thereof, this season. No matter how good the offense is, it won't matter if the defense can't get off the field. That's why the Bills need their current defensive roster to step up, otherwise they could waste another season with Allen as their leader and biggest strength.— Sign up for OnSI’s Free Buffalo Bills Newsletter —Add us as a preferred source on GoogleFollow