DALLAS — Sitting behind a quarterback who has not missed a single game since joining the Dallas Cowboys three years ago doesn't mean backup Cooper Rush can take it easy. In reality, he has to be ready for anything.

Prescott has started 48 consecutive games since the Cowboys drafted him in Round 4 of the 2016 NFL draft. Since taking over for a broke-back Tony Romo in the third preseason game of that year, Prescott has not looked back. Even though the two-time Pro Bowler's combination of durability and talent means Rush has a fat chance seeing the field during consequential action, the former undrafted field general from Central Michigan remains ever ready.

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"That's just part of the job as the backup," Rush said July 13 at SportsCon. "You practice all week and you study the game plan. You know it like the back of your hand. When the opportunity comes, you've got to fill in for your team, play well, and do your job."

The only action Rush has seen is garbage time in his rookie season in 2017. In a 40-10 blowout of the San Francisco 49ers, Rush completed 1-of-2 for two yards and rushed twice for 13 yards. In a 39-7 loss to the Philadelphia Eagles, Rush threw a solitary incomplete pass. The 6-3, 225-pound signal caller saw no action in 2018 when Dallas went 10-6 and won the NFC East.

Even though Rush's growth as a quarterback is not readily evident due to his lack of playing time, Rush insists that he has improved over the past two seasons.

"Every year you just keep gaining confidence with your own scheme and with how NFL defenses play, the speed of the game, all that stuff you hear about," said Rush. "It's real and coming all together, and in minicamp and OTAs I've felt really comfortable and really looking forward to training camp and so on."

Part of what has helped Rush gain more confidence ahead of his third season is new quarterbacks coach Jon Kitna. The former Cowboys backup from 2009-11, one of four stops in his 16-season career, has helped Prescott. However, the trickle down effect of how Kitna has impacted the rest of the position group has already impressed Rush.

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Said Rush: "He fits in the quarterback room really well. He is awesome to work with, a guy that brings 16 years of NFL experience. He's seen it all. So, he can constantly throw out advice that he's seen before. He's big on the fundamentals of quarterback footwork. He's really helped me personally with that stuff, working on arm strength, and seeing the game the right way."

Rush could use all the help he can get. The "anything" he has to be ready for isn't just Prescott missing time; it's former 2018 fifth-round pick nipping at his heels and taking his job as backup quarterback. With both Rush and White fighting for reps behind Prescott, the 25-year-old long eschewed an adversarial approach to White and instead considers him a "buddy" in the process.

"Mike is a great guy, fun to work with," Rush said. "We're buddies and we love to compete. Really looking forward to this preseason."

As to White endeavoring for the backup spot behind Prescott, Rush knows it is the nature of pro football.

"It's the NFL. Every day there is competition," said Rush. "There's someone out there trying to compete with you for your job. And that's the nature of the position of quarterback. That's how it's always been and that's how it's always going to be."

When camp opens July 26 in Oxnard, Calif., Rush will have to be ready to take over for Prescott and keep White at bay along with anything else the nature of being a Cowboys backup throws at him.

Do you think the Cowboys have a viable backup at quarterback with Cooper Rush? Share your thoughts on the backup battle this summer with Mark on Twitter @therealmarklane.