At last, Kaepernick has his receiving corps intact, just in time for the stretch run.
Boldin caught nine passes from Kaepernick, Crabtree made his long-awaited debut six months after Achilles tendon surgery, and the 49ers pressured the Rams defense from every angle.
Next up: NFC West nemesis Seattle in a week at Candlestick Park.
"We're very eager," safety Donte Whitner said. "They embarrassed us last time."
Kaepernick went 19 of 28 for 275 yards and Frank Gore ran for a 3-yard touchdown as the reigning NFC champion Niners (8-4) boosted their position in the playoff picture. Crabtree had that 60-yard catch, while Davis hurdled into the end zone on a 17-yard touchdown reception.
"I wish I would have scored," Crabtree said. "I was supposed to take that to the house."
With Hall of Famer Jerry Rice in the house, Boldin had six receptions in the first half on the way to his second-most productive game of the year behind his 13-catch performance in the season opener against Green Bay. He, too, teased Crabtree about not getting into the end zone.
"We give him a pass on that one; Thanksgiving was this week," Boldin quipped.
Crabtree, San Francisco's leading wide receiver during last season's Super Bowl run, had two catches. Just having him on the field kept the St. Louis defense from focusing all its attention on Boldin and Davis.
Davis displayed his athleticism with a new signature move, and did so not once but twice: a high hurdle over defenders. He led with his right foot while leaping over safety Rodney McLeod in the first half, then again to reach the end zone on his team-leading 10th touchdown catch. Davis also was tackled by T.J. McDonald with a prolonged, painful grab to his crotch. That was a first in his career.
"I was hurting," Davis said.
Clemens went 19 of 37 for 218 yards with a late TD pass in a dismal afternoon for the Rams (5-7), who were trying for their first three-game winning streak of the season.
"There were some plays out there that we had opportunities to make which would have gotten us into a little bit of a better rhythm offensively," Clemens said. "We didn't make them."
A year after the teams left Candlestick with a 24-24 tie, the 49ers methodically took care that it didn't happen again. They made it consecutive commanding victories in a short week following a 27-6 win at Washington on Monday night that snapped a two-game skid.
"All the pressure, all the high stakes this time of the year, I thought our guys answered the bell on that," coach Jim Harbaugh said.
While Kaepernick was sacked four times, Robert Quinn and the opportunistic Rams defense failed to make the game-changing plays it had the past two weeks -- even when 49ers left tackle Joe Staley was lost to a right knee injury early in the game. The St. Louis defensive line had scored touchdowns in each of the past two games.
The Rams thwarted drives with costly penalties, settling for a 43-yard field goal by Greg Zuerlein just before halftime in their best drive of the half. Zuerlein kicked a 34-yarder in the third quarter.
After a debated 15-yard personal foul penalty on Jo-Lonn Dunbar when he ran into a sliding Kaepernick, the quarterback completed a 23-yard pass to Davis. Dawson kicked a 32-yard field goal. He added a 43-yarder early in the second period, then a 24-yard field goal in the third.
The Rams managed 11 total yards in the first quarter and 73 in the first half. The 49ers held the Rams in check before the second-team defense surrendered Brian Quick's 3-yard touchdown catch with 18 seconds remaining.
Crabtree had a pair of penalties in San Francisco's opening series, an illegal block to the back and an offensive pass interference.
"I had to get those jitters out," he said.
49ers TE Vance McDonald injured an ankle in the first quarter. ... St. Louis lost left tackle Jake Long late in the third quarter to a concussion after he collided into running back Zac Stacy, who played after dealing with concussion-like symptoms following a win against the Bears. Rams C Scott Wells also suffered an ankle injury.