49ers-Texans: What to watch for

A pair of .500 teams square off for Sunday Night Football at Candlestick Park as the San Francisco 49ers (2-2) host the Houston Texans (2-2).

The 49ers snapped a two-game losing streak at St. Louis last Thursday while the Texans need a road win to avoid a third-consecutive loss.

Here are a few things to watch for on game day:

Protecting Kap

The 49ers offensive line has allowed 10 sacks on Colin Kaepernick through four games, while Texans pass rushers J.J. Watt, Whitney Mercilus and Antonio Smith have combined for 9-1/2 sacks in that time.

Right tackle Anthony Davis (shoulder) is questionable for Sunday’s game, so Adam Snyder will start if he can’t go. Either way, the importance of getting blocking help at tight end and running back increases ten tenfold against a fierce pass rush.

Look for a tough battle in the trenches. Whoever wins here is going to win the game.

The 49ers can keep the Texans’ defense honest by reestablishing the running game that bowled over the Rams defense for 219 yards last week.

The battle underneath

The All-Pro linebacker corps is missing Aldon Smith (rehab) while Patrick Willis (groin) is not 100 percent either. Michael Wilhoite, Dan Skuta, and Corey Lemonier, though, have filled in amicably.

The unit will be tested underneath by tight ends Owen Daniels and Garrett Graham who have combined for 30 receptions and six touchdowns this season.

The tandem is a favorite of quarterback Matt Schaub in the red zone, but everyone at the second level will have to account for both players on every down.

Expect lots of collisions.

Baldwin rising

The humble former 2011 first-round pick Jon Baldwin can make his case for the No. 2 wide receiver spot with a solid game.

The 6-4, 230-pound former Chiefs prospect already outperformed his trade-mate A.J. Jenkins last week with two catches for 19 yards on two targets. This after being inactive the first three weeks while he acclimated to the 49ers playbook following the preseason deal for Jenkins.

The 49ers have gotten low catch production out of Kyle Williams, Marlon Moore, and Quinton Patton (foot) who’s now hurt.

Meanwhile Mario Manningham (knee) isn’t due back realistically until after Week 8 while Michael Crabtree (Achilles) is out until at least early Dec.

Baldwin averaged 14.1 yards per catch in 29 games in Kansas City and uses his size to get off the line, something the rest of the receivers aside from Anquan Boldin have struggled to do.

Head coach Jim Harbaugh praised Baldwin at this week’s press conferences — which really doesn’t mean much — and the 49ers need him to step up now.

Notes

Future Hall of Famer Ed Reed missed Houston’s first two games with injury, but has no interceptions in the two games he’s been active for since; his last pick was in the Super Bowl off Kaepernick. … Kickoff is at 5:30 p.m. and the game can be seen on NBC.

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