GREEN BAY, Wis. - In a game billed as a marquee showdown, the Ravens' defense was knocked out.

In a contest there for the Ravens' taking, quarterback Elvis Grbac was down for the count.

Helpless against Packers quarterback Brett Favre and hapless with a groggy Grbac, the Ravens were floored in a 31-23 loss to Green Bay in front of 59,866 at Lambeau Field yesterday. The loss puts the Ravens (3-2) in a three-way tie for second place in the AFC Central, dropping them a half-game back of the Pittsburgh Steelers.

Grbac suffered a concussion on a hit by Santana Dotson that forced his second-quarter fumble, and he never recovered. He had a hand in three of the Ravens' four turnovers before bowing out midway in the fourth quarter. Grbac's injury is considered day-to-day.

Meanwhile, the Ravens' defense whiffed in its shot at one of the game's top quarterbacks, giving up a season-worst 337 yards passing and three touchdowns to the elusive Favre.

Working primarily out of the shotgun, Favre drove the ball at will and put the finishing touches on his artful performance with a 2-yard pass to tight end Bubba Franks that staked the Packers to a 31-10, fourth-quarter lead, enabling Green Bay to withstand a late Ravens rally.

Chasing Favre and his receivers took a toll on the usually stingy Ravens, who surrendered their most points since the second game of last season against Jacksonville.

"Every time I looked up, he was scrambling," Ravens safety Rod Woodson said. "We were playing all our defenses against him. It seemed like every play on defense somebody was making a mental error or not doing their jobs. It was very frustrating. Very frustrating."

Frustration for the offense slowly set in after that decisive blow to Grbac.

Trailing 10-7 with 3:13 left in the first half, the Ravens were at the Green Bay 19-yard line when Dotson jumped to the inside of right guard Bennie Anderson and changed the game for Grbac. Dotson forced the ball out of Grbac's cocked arm, sending him flat on his back with a head-on hit and snapping Grbac's head against the turf.

After that fumble, Grbac threw interceptions on the next two possessions and could produce one field goal before leaving eight minutes into the fourth quarter.

"After I got hit, it was a really strange feeling," a glassy-eyed Grbac said in the locker room. "It was almost like an out-of-body experience. I just couldn't focus on anything.

"As the game went on, like in the fourth quarter, it was like my body just wanted to go to sleep. Then it was my mind shutting down. I was just trying to hang in there and make some plays. This was probably the worst one [concussion] I've ever had."

Before the hit, Grbac was 6-for-10 for 87 yards and was sharp on the first drive. Capitalizing on a Green Bay fumble, Grbac hit Qadry Ismail for 47 yards and then connected with Travis Taylor for an 18-yard touchdown, putting the Ravens ahead 7-0 4:22 into the game.

The Ravens were marching on their second series as well, driving to the Packers' 40, where fullback Obafemi Ayanbadejo fumbled. Green Bay converted that turnover to tie the game on the first play in the second quarter, when Franks caught a 2-yard touchdown pass. That was the first touchdown allowed by the Ravens' defense in 134 minutes, 45 seconds.

"We had an opportunity to go up 14-0, and we turned the football over," tight end Shannon Sharpe said. "We are not talented enough to turn over the football and win. It's as simple as that."

The Packers (4-1) continued to roll in their four- and five-wide-out formations, going ahead on Ryan Longwell's 33-yard field goal and increasing the lead to 17-7 with two seconds left in the second quarter, when Favre zipped an 8-yard touchdown pass to Baltimore native Antonio Freeman. Favre bought time by rolling to his right while Freeman became wide-open with a slight push-off on cornerback Duane Starks.

"The way he played today explains why he's the three-time MVP quarterback," Starks said.

Favre's effort left a prideful Ravens defense stunned.