Josh Rosen didn’t exactly shine as the last first-round QB of the 2018 NFL draft to take the field during preseason action, but he did show plenty of promise for the Arizona Cardinals as he navigated constantly collapsing pockets and delivered catchable balls to receivers whose hands had other ideas.

After leading the Cardinals out of the tunnel, the No. 10 overall pick was under center for all but one drive in the first half and finished his night at 6-of-13 passing for 41 yards and no touchdowns or interceptions. The furthest the Cardinals reached on the field during Rosen’s four drives was a 22-yard trek to the Chargers’ 39 yard line.

While not disastrous, that line is certainly underwhelming for the debut of a player who said every team that didn’t draft him made a mistake. But that’s not the whole story.

Josh Rosen’s highlights of the night

More than half of Rosen’s passing yards came on a single play, an impressive 21-yard pass under pressure. As you can see above, Rosen kept his eyes downfield as he moved out of the pocket and delivered a strike to tight end Gabe Holmes downfield.

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Rosen’s first completion also showed some promise, quickly finding Christian Kirk and standing tall through the pass before getting popped by Melvin Ingram.

Operating with the Cardinals’ second unit, Rosen didn’t get much time to show off the talent that had him considered one of the steals of the drafts. However, considering the state of the Cardinals’ offensive line, that might just be something Rosen has to get used to for the time being.

Josh Rosen’s lack of support

Chargers pass rushers were a common feature in the Cardinals backfield and left little to no time for Rosen to find receivers downfield, plus several plays started off on a bad foot due to low snaps out of shotgun. Cardinals receivers also didn’t do Rosen many favors, as the quarterback saw at least two catchable passes dropped.

“I think he did well, I really do,” Cardinals head coach Steve Wilks said in a halftime interview. “We’ve got do a much better job of protecting him in the pocket to complete those passes.

The Arizona offensive line came in at 23rd in the NFL in Yahoo Sports’ rankings last month, with most of the praise going toward adequate run blocking and some concern expressed over the unit’s depth. That’s not great news when you’re the quarterback of the No. 2 offense, and it showed on Saturday.

To be clear, Rosen wasn’t entirely without fault; he nearly threw a pick-six to Chargers cornerback Desmond King in one instance. Fellow top picks Baker Mayfield and Sam Darnold were quite impressive in their debuts, and Lamar Jackson and Josh Allen flashed even better highlights than Rosen’s.

Rosen is certainly not the first quarterback to play with a sub-par offensive line this preseason, but performances like his on Saturday are also why preseason is a precarious time to praise or bury quarterbacks. It was less than one half of one game, and the Cardinals have plenty of time to develop their QB of the future.

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