A successful second-half rally helped Washington Football Team defeat the Pittsburgh Steelers 23-17 and crush the home side's hopes of an undefeated regular season.

Pittsburgh were leading through the game – including being up 14-0 just before half-time – until Dustin Hopkins’s 45-yard field goal with two minutes left in the match put Washington up 20-17.

Hopkins came up with the goods again with 17 seconds remaining as he booted home another 45-yarder, helping his side to improve to 5-7 and ensuring the 11-1 Steelers will need to win on Sunday in upstate New York to qualify for the post-season.

They will face the Buffalo Bills, who defeated the San Francisco 49ers 34-24 in Phoenix.

Buffalo quarterback Josh Allen had a career night as he went 32 of 40 throws for 375 yards, four touchdowns and no interceptions.

The loss means San Francisco will struggle to secure a play-off spot and could finish their campaign with a losing record, while the Bills are 9-3 and top the AFC East.