In the five games since, Siemian has been one of the worst quarterbacks in the National Football League.
According to a source, if the Broncos do make a change it will likely be to former first-round pick Paxton Lynch. Siemian, who was 19 of 36 for 198 yards with a touchdown and the three interceptions against the Chiefs, said it was not his job to decide who starts against the Eagles. Among the 29 quarterbacks with at least 200 dropbacks this season, his -0.08 Passing Net Expected Points per dropback rank fourth-worst. Those numbers alone make Siemian "benchable", but what's more alarmingly, is the fact that the Broncos have gone just 1-4 in during that time.
The Broncos also fumbled twice and Joseph said the five turnovers were "unacceptable".
Although 17 of Siemian's 19 sacks during this slump have come with Denver in three-receiver sets where there's no help for his struggling tackles, Joseph defended McCoy, who last week left Allen Barbre to block Joey Bosa mostly by himself in his first game at right tackle since 2009. Siemian threw three interceptions on the night. "I don't blame guys for being upset because again, this football team has worked hard and guys worked hard last night to win the football game and it didn't happen".
"That wouldn't be fair to our football team or Paxton", Joseph said.
Broncos president of football operations/general manager John Elway said Osweiler could undergo "football rehab" with the Broncos. "So, in my mind that was appropriate at the time", Joseph said. Lynch was a first-round pick in 2016 after a prolific career at Memphis.
Asked whether Broncos offensive coordinator Mike McCoy has protected Siemian well enough recently, Joseph said: "I think he has, but I've said all along we can coach and play better".
"That's his job as the quarterback".