Two teams that seemed to be steamrolling toward a clash of unbeatens now find themselves looking to recover.Although the Kansas City Chiefs and Buffalo Bills are each 4-1 and leading their respective divisions in the AFC, each will be coming off their first defeats Monday at Orchard Park, N.Y. The game got pushed back four days because of dominoes related to COVID-19 developments and kick off at 5 p.m. ET.Each team allowed 40 points in their recent losses, creating deficits neither Patrick Mahomes nor Josh Allen could overcome quarterbacking the Chiefs and Bills, respectively.Mahomes was constantly hounded and sacked three times by the Oakland Raiders in a 40-32 loss, leaving him to scurry quickly from the pocket and often look over the top in third-and-long situations.”We can’t just rely on the big play,” said Mahomes, who completed a season-low 51.2 percent of his passes against Las Vegas. “We have to execute at a high level and when the big play comes, you have to hit it.”Although Mahomes often clicks on those looks, the end of a 13-game winning streak — including playoffs, highlighted by last season’s Super Bowl victory — proved he is mortal.Now, Mahomes must move on from a setback without experienced receiver Sammy Watkins (hamstring) and guard Kelechi Osemele (knee).”I can help with different calls and putting people in better positions,” Chiefs coach Andy Reid said. “Everyone has a little piece of the pie here.”That includes the Kansas City defense, which permitted 20 points or less in each of the Chiefs’ first four games before allowing 490 yards to the Raiders, including five chunk plays of 40-plus yards.Botched execution hurt the Bills in their first defeat and now they have a short week to recover after falling to Tennessee, 42-16, on Tuesday. Two interceptions and long returns Buffalo gave up on special teams proved fatal against a virus-plagued opponent that had practiced only once in 12 days.One of Allen’s interceptions bounded off the hands of a receiver, but the Bills quarterback will still be looking to rebound against the Chiefs. That will be a collective effort, though, after his defense could only get him the ball twice in the final 17 minutes against Tennessee.Allen relies on one of the NFL’s hottest receivers, Stephon Diggs, who ranks second in the league with 509 receiving yards. Allen, meanwhile, ranks second in passing yards (1,589) and touchdown strikes (14).