When Byron Leftwich prepared for his first NFL start at quarterback – in the fourth game of his rookie season with the Jacksonville Jaguars – he envisioned greatness.
"I was going to throw for five touchdowns, four-hundred-something yards, because that's your mindset," the Cardinals quarterbacks coach said.
When Mike Glennon prepared for his first NFL start at quarterback – in the fourth game of his rookie season with the Tampa Bay Buccaneers – the excitement hit him hard.
"I was like, 'Here we go,' " the Cardinals' reserve quarterback said. "There were a lot of emotions."
Now Leftwich and Glennon are helping Josh Rosen prepare for his first NFL start, which happens to be the fourth game of Rosen's rookie season.
Rosen's first practice as starter came Wednesday. Coach Steve Wilks said Rosen did well digesting the installation of the game plan and that the team was "feeding off his energy." Wilks talked about the emphasis on not overloading the rookie.
But if emotions were toying with Rosen at all, he didn't show it when he spoke. He acknowledged he might've been hyped "a little bit" with the thought of getting underway what he hopes is a long career, but the reality of this week's practice – and the Seahawks – tamed that quick enough.
His confidence is, as always, high. But "regardless of how much confidence you have or not, if you're not throwing the ball to the right receiver, getting into the right run play, it doesn't matter," Rosen said.
Still, as a first-round pick, Rosen has expectations. Just like Leftwich, who was the seventh overall pick in 2003, but was set to sit the bench behind Mark Brunell. But Brunell got hurt Week 3, and Leftwich got the call for a road trip in Houston.
It didn't go perfectly, not after a 24-20 loss for the Jaguars. Leftwich completed 17-of-36 passes for 231 yards, a touchdown and three interceptions. Bumpy as it was, Leftwich shrugged it off, beating the Chargers at home the next week, 27-21, in which he threw for 336 yards, two touchdowns and no picks.
And for all the bumps he endured as a rookie, thinking it is getting difficult "never crosses your mind."
"You never doubt yourself, even if you're fooling yourself," Leftwich said. "There's nervous energy there, who are we kidding? You're in the National Football League. At the same time, we were probably built for this. We were built to go out to play and have success. The kid (Rosen) is working his tail off, he's willing to be coached, and it's a blessing to be coaching a kid like this."
Glennon's pedigree is different than his coach or his quarterback teammates. Glennon was a third-round pick, tapped in 2013 to replace Josh Freeman before a Bucs' home game against – coincidentally – the Cardinals.
Glennon was confident but he also understood the hill he was attempting to climb. He threw an early touchdown pass and the Bucs carried with them a lead deep into the fourth quarter – until Glennon threw two interceptions to cornerback Patrick Peterson, setting up 10 late points in a 13-10 Arizona win.
"The other day, I was looking at the scoreboard (at State Farm Stadium) and saw Patrick Peterson has 20 career interceptions and thought, 'Damn, I make up 10 percent of those,' " Glennon said.
Glennon – who finished his rookie year with 19 touchdown passes and only nine interceptions -- praised Rosen's preparedness at such a young age, saying Rosen knows many things already it took Glennon a few years in the league to learn. Rosen's top-10 status likely makes this week's transition easier too.
"I think with (Josh) being a first-round pick, it gave him more time, because the reality of the business is, a first-round pick, chances are (you'll play soon)," Glennon said. "He's prepared for that. I am sure he'll have a lot of different thoughts and emotions. This is something he's worked for, prepared for, probably dreamed of his whole life. Here it is."
Indeed, Rosen noted Wednesday that becoming an NFL quarterback was less of a decision and "more of a dream that slowly gets realized over time." But since he arrived in Arizona, he has been deliberate in learning the playbook, earning praise from Leftwich and Wilks for his study habits.
"I will not run a play on the football field unless I know why we are running it and what we are trying to accomplish," Rosen said. "That's just how I function. I don't run a 4.5, so if things go bad, I can't just hit the exit button. I like to understand the playbook in its entirety."
Rosen will also benefit from getting so many first-team reps in the offseason, working with the starters during the Cardinals' efforts to preserve Sam Bradford's rehabbed knee. That's when he first developed chemistry with the offensive line, and in preseason work, he's already had snaps throwing to all the receivers save Larry Fitzgerald – a relationship that shouldn't be hard to build, given Fitzgerald's experience working with so many different quarterbacks.
That should help Sunday against the Seahawks – a team that unveiled their quarterback of the future, Russell Wilson, for the first time at State Farm Stadium in 2012 against the Cardinals.
"With so many young quarterbacks that have just had startling entries into the league and done so many things, we're going to count on Josh being on it and whipping the ball around like he can," Seahawks coach Pete Carroll said.
Rosen, 21, was only 6 when Leftwich took the field against the Texans all those years ago. Leftwich said with a chuckle he casually dropped this week to Rosen the info that he too started his fourth NFL game.
"He's like, 'Really?' " Leftwich said with a smile. "I'll give him some more throughout the week, what to do, what not to do. But we'll have fun with it."