Kelly has confirmed that Nick Foles will be his starter in the 2014 campaign, but feels that the way the game is played he may need to add another signal caller to the mix for his team to be successful.
"It's a very, very difficult position to play. Everybody is hitting you, and they're protected by rules but they also still take some unbelievable shots," Kelly told the club's official website.
"I think, if you're going to last as a team, you'd better have two."
The Eagles had their 2013 season ended by the New Orleans Saints in the Wild Card round of the playoffs on Sunday.