The Falcons trailed 27-16 going into the fourth quarter, and took the lead through a 1-yard touchdown run by Devonta Freeman, followed by a 5-yard pass from Matt Ryan to Aldrick Robinson. Having failed on the two-point conversion following Freeman's touchdown, they tried for two points again after Robinson's catch with the aim of securing a three-point lead going into the last four minutes of the game; however, Chiefs safety Eric Berry intercepted Ryan's attempted pass and returned it all the way to the Atlanta end zone for a defensive two-point conversion that gave Kansas City a 29-28 lead that they were able to defend for the remainder of the game.. How many points were the Falcons behind at the start of the fourth quarter?