''I feel a lot better than I did yesterday,'' Smith said Monday. ''But it still doesn't feel good, at all, losing. Still embarrassed about how we've been playing offensively.''
Smith made two catches Sunday and was visibly frustrated on the field for much of the afternoon. The 49ers managed just 196 total yards, with 47 coming on a long pass to Smith in the fourth quarter. However, that catch didn't lead to points as San Francisco wound up turning the ball over on downs.
''My body language was horrible at times. I should never let my frustrations show, especially to (reporters),'' Smith said. ''That's not a good thing. I'll work at that. ... To be honest, we work too hard to go out on Sundays and play like that. (Coach Jim) Tomsula doesn't deserve this. The fans don't deserve to watch the way we play.''
Smith, who signed a five-year deal that could be worth as much as $40 million, has nine receptions for 185 yards in four games. His lone touchdown catch came in the second half of a blowout loss to the Pittsburgh Steelers in Week 2.
''When you work like we do, we work hard, success has to come,'' Smith said. ''It hasn't been coming, but it just has to happen. Just stick by that belief and hope we can get this thing going.''
Tomsula said, ''We need to use him and we need to get him more involved. That's on the checklist.''
The Packers' defense was intent on stopping the run by keeping safeties close to the line of scrimmage. Running back Carlos Hyde had just 20 yards on eight carries in his first home game since running for 168 yards and two touchdowns in the season-opening win over the Minnesota Vikings.
Kaepernick was the team's leading rusher, netting 57 yards on 10 carries. Running back Reggie Bush returned after a two-game absence with a calf injury, registering one run for no gain.
The 49ers were unable to take advantage of Green Bay's game plan by utilizing Smith's speed, with Kaepernick completing just one of seven throws that went longer than 10 yards.
Kaepernick's 67.7 passer rating through four games is the lowest since he became the full-time starter midway through the 2012 season, when he led San Francisco to the Super Bowl.
''We have to find our rhythm,'' Kaepernick said Sunday. ''We have to get back on track and string plays together. When we do that, we have produced successful drives. It's getting those plays to string together where we've struggled thus far.''
Tomsula said Monday that wide receiver Quinton Patton suffered a concussion Sunday and is going through the league-mandated concussion protocol. There's no timetable on his return.
Patton had the 49ers' second-longest play of the game Sunday when he took a shovel pass from Kaepernick and ran 40 yards up the left sideline in the second quarter, setting up a 33-yard Phil Dawson field goal.
San Francisco is at the New York Giants (2-2) on Sunday.
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