The magic number is 8. The Eagles are one victory from an 8-1 start, their statistical springboard to greatness, when they oppose the Denver Broncos Sunday at Lincoln Financial Field (1 p.m., CBS, WIP 94.1-FM). The Eagles won NFL championships in 1949 and 1960 and reached the Super Bowl in the 1980 and 2004 seasons when they started 8-1. In 1949 the Birds won their first NFL title with an 8-1-1 start. The Eagles also put their six-game win streak on the line against the Broncos (3-4), who have lost three straight games and benched turnover-plagued starting quarterback Trevor Siemian in favor of Brock Osweiler. The Broncos average just 18.1 points. With Siemian running the offense they’ve totaled 35 points in three road games, all losses, and have tallied 20 or more points just twice this season. The Broncos outgained the opposition in three of their setbacks but averaged three giveaways in their four losses.