He looked and learned.
In the 2015 opener, the spectator will be Brady if his four-game suspension isn't overturned on appeal. Garoppolo, the heir apparent to the New England Patriots quarterback, should get his chance much sooner than expected.
Is the second-year pro from a second-tier school up to it?
''I have confidence in the kid,'' said Jeff Christensen, a quarterback tutor who has worked with Garoppolo for nearly 10 years.
In Garoppolo's favor: a full season plus this offseason learning from Brady, the mediocre competition in the AFC East, and playing for coach Bill Belichick.
Working against him: not having faced major college teams, a lack of NFL experience, and a national spotlight on him as the replacement for a star whose reputation was tarnished in the scandal known as ''Deflategate.''
And what about the team? Could Brady's suspension for his role in deflating footballs in last season's AFC title game seriously harm New England's chances to repeat as Super Bowl champions?
Last season, the Patriots started just 2-2 even with Brady. Then he led them to the title.
In 2008, they went 11-5 with Matt Cassel at quarterback after Brady suffered a season-ending knee injury in the first quarter of the first game.
''The best example in the history of football is right in front of you,'' Christensen said Tuesday. ''Didn't (Drew) Bledsoe get hurt in Tom's second year?''
Bledsoe suffered a serious chest injury against the New York Jets in the second game and didn't play again in the 2001 regular season as Brady led the Patriots to the Super Bowl championship.
The common denominator is Belichick, who keeps winning despite frequent roster turnover. He thought enough of Garoppolo coming out of Eastern Illinois to use a second-round pick on a player who threw 53 touchdowns with nine interceptions as a senior. And he can simplify the game plan for Garoppolo.
''Growing from being a rookie in minicamp to where I am now, I feel a lot more confident,'' Garoppolo said five days before the Patriots' 28-24 Super Bowl win over the Seattle Seahawks.
''He's been practice player of the week for us a number of weeks, probably could've been more, for the look that he gives the defense,'' Belichick said of Garoppolo's role mimicking opposing quarterbacks.
Success would have to come in the spotlight. The Patriots host the Pittsburgh Steelers in the kickoff of the NFL season on Sept. 10. New England will be at Buffalo and then host Jacksonville in the weeks following.
Then comes a bye, an extra week for Garoppolo to prepare.
The fourth game is at Dallas and Tony Romo, another Eastern Illinois quarterback.
If the four-game suspension stands, Brady would return Oct. 18 at Indianapolis, the team that complained about the use of deflated balls in its 45-7 loss in the AFC championship game.
But Brady can participate in all offseason activities with Garoppolo nearby to soak up whatever he can.
''In practice, when he's standing behind Brady he's going through the exact same reads Tom is and seeing exactly the rhythm of how he does it,'' said Christensen, a former quarterback at Eastern Illinois drafted in the fifth round by Cincinnati in 1983. ''If you're really good mentally, you can get a lot of value out of that.''
When he first worked with the teenage Garoppolo, who was making the transition at a suburban Chicago high school from linebacker to quarterback, Christensen showed him video of Brady.
''Everything I taught was based off of what Brady does technique-wise,'' Christensen said.
As an NFL rookie, Garoppolo played in six games. He completed 19 of 27 passes for 182 yards, one touchdown and no interceptions.
Garoppolo entered that 41-14 loss at Kansas City that dropped New England to 2-2 with about 10 minutes left after Brady threw an interception that was returned for a touchdown.
''Anybody that wonders if Jimmy can do OK, I would just say this,'' Christensen said. ''Go put on that Kansas City film. He made some good, accurate throws.''
But it remains to be seen if he can succeed as a starter with a lot more pressure and attention.
''I think he'll play well,'' Christensen said.
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