49ers-Browns: Matchups to watch

Aldon Smith leads the 49ers and ranks second among NFL rookies with 5.5 sacks. And on Sunday at Candlestick Park, he'll go up against Joe Thomas, whom many consider to be the top offensive lineman in the league.
Tale of the tape
Smith (99): 6-4, 258, Missouri, Rookie
Thomas (73): 6-6, 312, Wisconsin, Fifth seasonIn six games, Thomas has surrendered 1.5 sacks. In 16 games a year ago, he surrendered four sacks. Thomas has been outstanding since entering the NFL as the No. 3 overall pick of the 2007 draft.Thomas has not missed an offensive snap in 70 games since coming into the NFL. In August, Thomas signed a seven-year, 84 million contract extension. With the strength throughout the 49ers' front seven, Thomas will likely be left alone to handle Smith in Sunday's game. It's important that the Browns provide ample protection for quarterback Colt McCoy, who has been sacked 13 times this season.McCoy is averaging a lowly 5.46 yards per passing attempt, and the Browns might need to hit on some big plays down the field to stay in the game. The Browns will rely on Thomas to keep the rookie away from McCoy.
"He's a good pass protector," Browns coach Pat Shurmur said of Thomas. "Obviously, he's a good run-blocker. He's what you're looking for from a left tackle. You don't tend to worry about him so much because he's such a good player."Now, we're going to get challenged this week for sure. So I think we're counting on him to have one of his better games against an opponent that's going to be a big challenge."Smith does not start for the 49ers, but he will enter the game in place of Parys Haralson at right defensive end in nickel situations.Other matchups worth watching
49ers left guard Mike Iupati (77) vs. Browns defensive tackle Ahtyba Rubin (71): The 49ers like to run to the left side behind 331-pound Iupati, and he'll have perhaps his stiffest challenge of the season. Rubin, a 330-pounder, might be the best player on the Browns' defense. The club signed him to a three-year, 27 million extension in the offseason with 18 million guaranteed. Rubin rarely comes off the field, as he stuffs the run and also adds quickness off the snap to get up the field as a pass-rusher. Rubin leads the Browns with three sacks on the season.49ers punter Andy Lee (4)kicker David Akers (2) vs. Browns return man Joshua Cribbs: The Browns have struggled on special teams, while the 49ers have excelled. That switch in fortunes has coincided with special-teams coordinator Brad Seely's move from Cleveland to the 49ers this season. Cribbs will be in the starting lineup at wide receiver, replacing Mohamed Massoquoi, who will miss the game with a concussion. Cribbs, the all-time NFL career leader with eight touchdown kickoff returns for touchdowns, will still be asked to make a healthy contribution in the return game, He ranks 12th in kickoff returns with a 25.0 average. Cribbs is also 12th in punt returns with a 10.8 average. Akers has done a good job of limiting the chances for the opposing kick returner. Twenty-two of his 37 kickoffs have been touchbacks. And the average start point for the opposition is the 21-yard line. Likewise, Lee's 44.4 net average is tied for the best in the league.