The rookie quarterback left Buffalo's game late in the third quarter after suffering an elbow injury and did not return as the Bills lost 20-13.
Nathan Peterman replaced Allen, engineering a 32-yard touchdown drive capped by a strike to Zay Jones for the score and a fourth-quarter lead. It all fell apart from there, though, as Peterman threw a crushing pick-six with the game tied and less than two minutes remaining. Peterman finished his afternoon by throwing a second interception on a tipped pass caught by Houston's Kareem Jackson to seal the Texans' win.
Allen, while under nearly constant pressure, managed to complete 10 of 17 passes for 84 yards while also rushing four times for 20 yards. He spent the remainder of Sunday with his elbow wrapped on the sideline, watching helplessly as the lead slipped away for the Bills in the final minutes.