49ers rip Rams 28-0 in season-opening win

The season-opening, prime-time victory, just like last year's Week 1 prime-time 20-3 romp over the playoff-bound Vikings, was headlined by a smothering defense and a potent rushing attack. With the defense limiting St. Louis to 10 first downs and 186 yards, quarterback Blaine Gabbert didn't need to stray from game-manager mode in his first season-opening start since 2013. Gabbert completed 22 of 35 passes for 170 yards with a touchdown before he was replaced by Colin Kaepernick with 2:31 remaining. The Rams haven't ranked among the NFL's top in points scored in 2006, and the 49ers made it appear they'll be fortunate to crack the top-30 this season. [...] the Rams offense was so dreadful that once-excited home fans might steer clear of their first game in Los Angeles in 22 years on Sunday against the Seahawks. On their first 14 possessions, before a game-ending kneel-down, the Rams had 11 punts, two interceptions and turned the ball over on downs. Unheralded quarterback Case Keenum, who arrived with a 79.8 career passer rating, did nothing to discourage the 49ers from following their defensive game plan: With the onus on the passing game, Keenum completed 17 of 35 passes for 130...