The Steelers traveled back home to take on the Broncos.  They would score first when D'Angelo Williams ran for a 2-yard TD for a 7-0 lead.  Not long before the Broncos scored 20 consecutive points starting with Brock Osweiler's 18-yard pass to Demyarius Thomas to tie the game at 7-7 and then taking the lead when Osweiler found Emmanuel Sanders on a 61-yard pass for a 14-7 lead.  In the second quarter, the Broncos increased their lead when Osweiler ran for a 7-yard TD (with a failed PAT) for a 20-7 game.  The Steelers would draw closer when Chris Boswell nailed a 24-yard field goal for a 20-10 game.  Though, the Broncos moved away when Osweiler found Thomas again on a 6-yard pass for a 27-10 game.  The Steelers started their reign of 24 consecutive points:  Starting with another field goal from Boswell from 41 yards out to make it 27-13 at halftime.  In the third quarter, Ben Roethlisberger found Antonio Brown on a 9-yard pass coming within 7 for the only score of the period, 27-20.  In the fourth quarter, the Steelers were able to tie the game up at 27-27 when Roethlisberger found Markus Wheaton on a 9-yard pass.  Finally, they wrapped up the scoring when Roethlisberger found Brown again this time on a 23-yard pass for the eventual final score of 34-27. The defense stood out again as they got 2 takeaways and 2 sacks.. How many yards was the longest TD pass of the first quarter?