The San Francisco 49ers‘ chances to win the NFC West took a massive hit with their 42-26 loss to the Los Angeles Rams on Sunday at Levi’s Stadium.

LA’s dominant outing was a reminder of how bad the 49ers’ injury situation is, and just how far they are behind the NFL’s elite teams. The Rams posted 401 yards and 42 points while facing very little resistance from the 49ers’ defense. And while the 49ers’ offense played well, mistakes ultimately put them in a hole they couldn’t dig out of.

Here are our takeaways from the 49ers’ fourth loss of the season:

49ers defense melts down

San Francisco’s defensive showing Sunday was the stuff of Robert Saleh’s nightmares. The Rams scored on their first three possessions. Then the 49ers buckled down and capitalized on a couple of mistakes from Rams signal caller Matthew Stafford and forced back-to-back punts. While they forced punts, the 49ers offense managed to hang around to make it a 21-7 game going into halftime. Then the wheels fell off for the defense. They allowed touchdowns on three of the Rams’ possessions in the second half, and they might’ve allowed a fourth had the Rams not run out the clock on their fourth and final possession. LA averaged 6.3 yards per play with kneel downs removed. They converted five-of-nine third downs and they were five-for-five in the red zone before the game ended with them at the 49ers’ 18. It was as bad as it gets for the 49ers defensively.

Mac Jones’ strong outing

Jones was good again Sunday, completing 33-of-39 throws for 319 yards with three touchdowns and one interception. The pick came late in the game on a fourth-and-4 with the 49ers in desperation mode. He tried fitting a pass in to Christian McCaffrey and Rams cornerback Emmanuel Forbes took it away. The more important thing for Jones on Sunday was that he looked more mobile than he has in weeks. He escaped pressure multiple times and found receivers after extending plays. That element has been missing from his game and he turned one scramble into a 19-yard completion to wide receiver Kendrick Bourne. He turned another one into a touchdown pass to tight end Luke Farrell.

Where is Nick Martin?

One of the 49ers’ biggest problems on defense was their inability to slow down the Rams’ 13 personnel grouping with three tight ends on the field. LA took advantage of Sam LB Luke Gifford who had a brutal day trying to hang with some of the Rams pass-catching TEs. It begs the question of where Martin, the 49ers’ rookie third-round pick, is at this point? He isn’t a typical Sam LB build, but San Francisco could have used some added athleticism. Either the 49ers drafted him to do something very specific, or they’re way down on a player they selected with a top 100 pick in this year’s draft. Neither scenario shines a kind light on the 49ers’ front office.

49ers get rare injury-free game … for now

Shanahan didn’t have any major injury updates from Sunday’s contest in his post-game press conference. Linebacker Tatum Bethune did exit for a few plays early in the game, but he was only out for part of one series. Monday’s conference call usually includes a few more injury updates from Shanahan once adrenaline wears off and players get to the facility the day after the game.

George Kittle showed up

Kittle had his best game of the year. He looked like he was single-handedly trying to drag the 49ers across the finish line. He hauled in all nine of his targets, made a couple of ridiculous contested catches, and turned in a sensational play for a touchdown where he stopped himself from going out of bounds and then dove for the pylon without stepping out. He finished with nine receptions for 84 yards and a touchdown.

Jauan Jennings makes up for early mistake

A fumble by Jennings on the 49ers’ second drive was the earliest sign that Sunday was going to be a rough one for San Francisco. Down 14-0, Jennings made a catch for 13 yards and a first down at the Rams’ 26. Then he fumbled. The Rams recovered and found the end zone nine plays later to go ahead 21-0. Jennings made up for it by posting six catches for 71 yards and a touchdown. He also might’ve drawn a pass interference on the 49ers’ first drive, but the officiating crew mostly kept their flags in their pockets Sunday. The moral of the story is that Jennings is looking healthier after dealing with a rash of injuries early in the year. Now he just needs to work on his ball security.

Where has Kendrick Bourne gone?

Speaking of wide receivers, Bourne had 142 yards in Week 5 against the Rams, and then another 142 in Week 6 against the Tampa Bay Buccaneers. In those two games he racked up his 284 yards on 15 catches. In four games since then he has eight catches for 111 yards, including just one for 19 against LA.

Christian McCaffrey’s 1,000/1,000 pace

McCaffrey was quiet on the ground Sunday with just 30 yards on 12 carries. He added 66 receiving yards on eight catches. For the year he’s up to 626 rushing yards and 692 receiving yards. While it wasn’t his best game from a production perspective, he’s still on pace for his second season with 1,000 rushing yards and 1,000 receiving yards. His current pace is 1,064 yards on the ground and 1,176 yards through the air. He’d become the first player to ever have two 1,000/1,000 seasons and he’d likely stamp his place in the Pro Football Hall of Fame.

A special teams miscue

What was once a regular problem for the 49ers has become a rarity, but there was a special teams mistake for San Francisco on Sunday. After Luke Farrell scored a touchdown to cut the Rams lead to 28-20, Eddy Pineiro’s extra point was blocked after backup center Matt Hennessy was railroaded by Rams defensive end Jared Verse. San Francisco probably should’ve been going for two in that spot anyway, but it was a rough flashback to last season when special teams mistakes swung games against the 49ers.

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