The Philadelphia Eagles concluded their preseason on Thursday with a loss to the Indianapolis Colts. What is not a foregone conclusion is who will backup quarterback Jalen Hurts.

The Eagles signed veteran Marcus Mariota this offseason with many projecting him to be Philly's No. 2 behind their MVP candidate signal-caller. The preseason performance of rookie Tanner McKee, who the Eagles selected in the sixth round of April's draft, has changed that narrative a bit.

There is speculation that McKee could dethrone Mariota as the backup and Eagles head coach Nick Sirianni's glowing postgame comments about the rookie makes things interesting.

“We drafted him because we liked him, and we liked the accuracy he showed on tape,” Sirianni said, via Myles Simmons. “We liked the decision-making he showed on tape, and he’s continued to show that throughout practice and games. He’s put three good games together, and so was excited to work with him. Really pleased with how he was this preseason.”

McKee entered camp battling Ian Book for the Eagles' third-string QB job and a spot on the final 53-man roster. The former has certainly locked that up with his preseason breakout.

McKee completed 39-of-72 passes for 453 yards and a touchdown in three preseason games and did not turn the ball over. Mariota got much less playing time but struggled with accuracy and didn’t do much to help his case.

The Eagles will likely start the season with Marcus Mariota as the backup but continued progression from Tanner McKee could push the veteran to the curb.