Jimmy Garoppolo might not be done learning from Tom Brady after all. 

The 49ers quarterback's former mentor was in similar shoes a decade ago, as Brady was working his way back from a torn ACL heading into the 2009 season. Brady's comeback campaign was successful by nearly all measures, as he threw for 4,398 yards and 28 touchdowns -- then the second-highest totals of his career. But, as ESPN's Bill Barnwell noted in a column Tuesday, Brady's 2.3 percent interception rate that season is his highest since his dominant 2007 season. 

Barnwell thinks Garoppolo's preseason performance is reminiscent of Brady's play from early in the 2009 season. 

"Garoppolo still seems unsure and unsteady when he's asked to plant his front foot and make a throw, especially under pressure," Barnwell wrote Tuesday. "The result is a loss of accuracy and velocity, along with a propensity to sail throws, all of which showed up on his interception against the [Denver] Broncos. ... Garoppolo's true interception rate is almost surely higher than Brady's, which could lead to an ugly number if his footwork is inconsistent over a full 16-game season." 

Barnwell noted that Garoppolo bounced back from his lackluster start in Week 2 of the preseason during his Week 3 start against the Kansas City Chiefs, but he believes Garoppolo's "footwork looks choppy" and the lack of pressure from the Chiefs' defense didn't test San Francisco's franchise QB all that much. Considering what coach Kyle Shanahan's system calls for from its signal-callers, Garoppolo's initial limited mobility could be a hindrance to the Niners' offense, according to Barnwell. 

 

"Shanahan could theoretically make it easier for Garoppolo by working out of shotgun more frequently and reducing the steps Garoppolo has to take in a given game, but it's more likely that the 49ers will start the year hoping that Garoppolo grows into the role," Barnwell wrote. "He'll get there, but the early returns could be ugly."

The 49ers open the season on the road against the Tampa Bay Buccaneers and Cincinnati Bengals, and only play one playoff team from last season (Los Angeles Rams) in their first eight games. The back half of the schedule isn't nearly as kind, with two matchups against the Seattle Seahawks, one against the Rams, Baltimore Ravens and New Orleans Saints. Each of those teams made it to the playoffs last year, and the non-playoff opponents the 49ers will face down the stretch are quarterbacked by Aaron Rodgers, Matt Ryan and Kyler Murray, the No. 1 pick in the 2019 NFL Draft. 

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Garoppolo becoming more comfortable as the season goes along could be a boon when the 49ers stare down a difficult second half of their schedule, but it not might matter much if he struggles in the first half. If San Francisco's Super Bowl-or-bust expectations are to be believed, a fast start is needed before the schedule ramps up in difficulty -- on paper, at least. 

A decade ago, Brady's Patriots finished the season 10-6 and won the AFC East, but were bounced in the wild-card round of the playoffs. The 49ers surely would take a similar outcome, but it will require Garoppolo to follow in his onetime mentor's footsteps once more.