The 49ers' decision to wait a little more than a month to start Jimmy Garoppolo until he could get a better grasp of the offense after giving the Patriots a 2018 second-round pick for him at the Oct. 31 trading deadline is being validated. The quarterback is breathing life into a downtrodden franchise. Garoppolo, whose four-year rookie contract expires after the season, has engineered two game-winning fourth-quarter drives during San Francisco's three victories in the three games he has started. The last 49ers quarterback to go undefeated in his first three starts was Y.A. Tittle in the early 1950s. Garoppolo also has consecutive 300-yard passing games, a feat that hadn't been accomplished by a 49ers quarterback since Jeff Garcia in 2000. In the three wins, Garoppolo, who still doesn't have a deep understanding of San Francisco's playbook, has completed 68.1 percent of his passes (77 of 113) for 1,008 yards with two touchdowns and two interceptions to post a 94.6 passer rating. The 49ers' failure to finish drives in the end zone has resulted in 15 made field goals over the last three games. As good as Garoppolo has been, much maligned Jaguars quarterback Blake Bortles has performed better during this span. Bortles is completing 71.4 percent of his passes (65 of 91) for 903 yards while throwing seven touchdowns without any interceptions to post a 128.6 passer rating in three December wins. Garoppolo faces his biggest challenge to date in Sunday's Week 16 contest against the Jaguars, who have the NFL's stingiest pass defense. Jacksonville leads the NFL in sacks (51), passing yards allowed (168.9 per game), opponent's completion percentage (55.9) and opponent's passer rating (65.2). The AFC South leaders are also giving up the fewest points in the league at 14.9 per game. The 49ers close the season on New Year's Eve with another tough opponent, the NFC West-leading Rams. Garoppolo's early success hasn't created a sense of urgency to sign him to a new deal. The 49ers seem content waiting until the season ends to have contract discussions. Regardless of what Garoppolo does for the remainder of the season, he is going to be a largely unproven commodity with only a handful of starts.