By Ed Molina (staff@latinospost.com) | First Posted: Sep 26, 2013 09:12 AM EDT

It was not suppose to be like this for the San Francisco 49ers, last year's Super Bowl runner-up, a media darling many National Football League media pundits predicted would return to the title game.

The 49ers looked like world-beaters after dismantling the Green Bay Packers 34-28 in Week 1, but have sputtered since, unable to score a single touchdown in their 29-3 loss to division rival Seattle Seahawks, and getting handled by the Indianapolis Colts 27-7 last week.

Colin Kaepernick has had difficulties, amid high expectations based on last year's performance and injury to key players at the skill positions, committing four turnovers against Seattle and going 13-of-27 with just 150 yards yards for the day, including an interception and a fumble.

The 49er defense has not been much help to the offense, currently ranked 29th in the league against the rush, giving up six rushing touchdowns for the year. Last year, the defense ranked third overall in the NFL, fourth against the rush, giving up seven rushing touchdowns the entire year.

"Football's not easy," said San Francisco head coach Jim Harbaugh. "There are struggles. That's one of the things you enjoy about the game, that there are struggles. We've got some adversity, there's no question about that. And we'll also have the opportunity of staring adversity in the face and whipping it."

The 49ers will have to play without OLB Aldon Smith, who was placed on the reserve non-football injury list on Monday, after entering rehabilitation for substance abuse as a result of his arrest on suspicion of DUI and marijuana possession.

"I am taking a leave of absence to address my health," Smith said in a statement on Monday. "I am sorry that I have affected my team, my family and the organization. I will do everything in my power to handle this situation the best way possible. I appreciate the support of the 49ers and our fans."

Smith's absence leaves a big hole for the defense to fill, who had earned 3 ½ sacks thus far this season and 19 ½ sacks last year to lead the NFC.

The Rams struggled against the Dallas Cowboys last week, gaining only 18 totals yards of offense in the first half (232 for the game) and went 0-for-12 in third down situations, converting one on the game's final play.

The Rams are hoping to bounce back against their NFC West division rival, building on last year's success - tying the 49ers 24-24 after going overtime in their Nov. 11, 2012 encounter, and later beating the 49ers 16-13 in overtime in the Dec. 2, 2012 rematch.

"All you have to do is put on a series here or a series there of our matchup last year, either one of the two games against the 49ers, and we'll have their attention," said St. Louis head coach Jeff Fisher.

Live Television Coverage
The San Francisco 49ers-St.Louis Rams Week 4 Thursday Night Football game can be seen on NFL Network, 8:25 p.m. EST.

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