GLENDALE, Ariz. -- For two-plus years, there was an element of unknown with what the New England Patriots had with quarterback Jimmy Garoppolo. That element of unknown has a different feeling to it after Sunday night’s season opener against the Arizona Cardinals.

Making his first career regular-season start, and doing so without top tight end Rob Gronkowski and starting left tackle Nate Solder, Garoppolo played an efficient, poised game in helping lead the Patriots to a 23-21 victory.

Garoppolo finished 24-of-33 for 264 yards, with one touchdown and no interceptions, and it took a missed 47-yard field goal by Cardinals kicker Chandler Catanzaro with less than a minute remaining to ensure he’d earn his first career victory.

But regardless of the kick, and ultimately the result, Garoppolo’s performance was an obvious positive development.

Some of the struggles Garoppolo had in the preseason, when he was holding on to the ball too long, didn’t show up often in the game. Part of that was because, as Garoppolo said a few weeks ago, the team hides things it plans to do in the regular season during exhibition contests.

With a game plan that focused on getting the ball out of his hands quickly, Garoppolo looked in command. He played with fire and emotion, much like Tom Brady, as reflected by his reaction following a 37-yard touchdown strike to receiver Chris Hogan on his first drive. Garoppolo was jumping up and down, pumping his fists and looking for a teammate to hug.

"I was fired up before the game. Amped up," Garoppolo said after a performance in which he was presented a game ball in the locker room in a scene that special teams captain Matthew Slater described as "sheer joy."

Much like Brady, who has shown a knack for delivering in the clutch, Garoppolo was impressive on the drive that put the Patriots ahead 23-21 in the fourth quarter.

His third-and-15 throw to Danny Amendola over the middle, for 32 yards, was one of his best of the night as he scrambled initially to keep the play alive. He later converted a third-and-3 attempt to running back James White.

So what do the Patriots have in Garoppolo?

It’s always dangerous to put too much stock in one game, but Sunday night couldn’t have gone any better.

"There was no doubt in this locker room that Jimmy could go out there and play," safety Devin McCourty said. "I'm happy he went out there, did it, and everyone can shut up now and watch the guy get better and grow and us keep improving as a team in the early part of the season."