BALTIMORE – As first impressions go, San Francisco 49ers coach Jim Harbaugh didn't care much for what he saw from his football team in its preseason opener against the Baltimore Ravens.
"We have some work to do," Harbaugh conceded after Thursday night's 23-3 loss.
Especially on defense. Although the 49ers didn't play standout linebacker Patrick Willis or starting linemen Ray McDonald and Glenn Dorsey, they still couldn't justify giving up 386 yards of offense, including an 80-yard drive on Baltimore's opening series.
"We're getting pushed around a little bit," Harbaugh said. "They were out there a lot of plays, looked a little tired and for ways to get off the field."
The Ravens held the ball for nearly 40 minutes and gained 237 yards on the ground on 48 carries.
"We didn't have a lot of our starters out there," cornerback Chris Cook said. "But we've got to be more physical up front and in all aspects of the game. I feel like we're going uphill right now, and we've got to work through some kinks."
It was the third time in three tries that Ravens coach John Harbaugh got the best of his brother, Jim. Baltimore previously defeated San Francisco on Thanksgiving 2011 and in the Super Bowl ending the 2012 season.
Each team played its starting unit for one series before the backups took over.
After Colin Kaepernick moved the 49ers 66 yards for a field goal, Joe Flacco made himself right at home in Gary Kubiak's variation of the West Coast offense, going 4 for 5 for 52 yards during a 10-play scoring drive.
"Ten plays in a new offense, that doesn't happen very often," wide receiver Steve Smith said. "We were high tempo, high paced, so that went well."
Kubiak, the former head coach of the Houston Texans, replaced offensive coordinator Jim Caldwell, now Detroit's head coach.
"The execution by the offense on our first drive was what we like to see," John Harbaugh said. "Our technique and assignments were sharp. It was good, fundamentally sound football."
Four different receivers caught passes from Flacco, the former Super Bowl MVP: Dennis Pitta for 14 yards, Jacoby Jones for 12, Kyle Juszczyk for 17 and Smith for 9.
"You expect to go out there and have a good drive," Flacco said. "You envision good things happening. You have a good idea of what plays you're going to run. It kind of went on schedule."
Ray Rice ran three times for 17 yards after receiving a warm ovation from the home crowd during pregame introductions. Rice has been suspended by the NFL for the opening two regular season games after being arrested for domestic violence in February.
Bernard Pierce will probably start while Rice is serving his suspension. Pierce ran for 37 yards, including a 2-yard touchdown run to end Baltimore's opening drive.
San Francisco had offensive coordinator Greg Roman back from last year, but he streamlined the playbook during the offseason in an effort to make it easier for Kaepernick to get the call in.
Kaepernick appeared relaxed at the helm during his lone series. He completed his only pass, 17 yards to tight end Vance McDonald.
"Ended up in the red zone with an opportunity to score a touchdown, so that's all that really matters," Kaepernick said. "The biggest thing for us was we were trying to get points on the board, regardless of how we get there."
San Francisco running back Frank Gore did not play. Rookie Carlos Hyde started and gained 39 yards on five carries.
Jonathan Martin started at right tackle for the 49ers in place of injured Anthony Davis (shoulder). Martin, who was in the center of the Miami Dolphins' bullying scandal involving former teammate Richie Incognito, came to San Francisco in an offseason trade.
Kaepernick's backup, Blaine Gabbert, went 3 for 11 for 20 yards and an interception.
Flacco's replacement, Tyrod Taylor, completed 13 of 21 passes for 116 yards and a touchdown. He also ran for 59 yards on five carries.
Justin Tucker kicked three field goals for Baltimore, including a 55-yarder that made it 16-3 late in the third quarter.
NOTES: The 49ers offense was without, among others, Gore, WRs Michael Crabtree and Brandon Lloyd. ... Ravens top draft pick C.J. Mosley had a sack.
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