There were troubling signs for the Washington Redskins' starting offense in its preseason home opener last night. But thanks to the spirited play of second- and third-stringers fighting for spots on the roster, the Redskins staged a late-game rally to defeat the Buffalo Bills, 20-19, before 60,004 at recently renamed Redskins Stadium.

With Daniel M. Snyder watching from the front row of his refurbished owners' box, third-string quarterback Casey Weldon tossed a game-winning, five-yard touchdown pass to Norman Miller with 3 minutes 5 seconds remaining.

The victory lifted Washington to 2-0 in the preseason, setting precisely the tone that Snyder expects from his $800 million investment. But as Coach Norv Turner knows, preseason wins won't count when Snyder evaluates his performance at the end of the season.

As evidenced in the first half last night, the starting offensive line continues to struggle in its efforts to give quarterback Brad Johnson enough time to throw. Moreover, starting tight end Stephen Alexander, among Johnson's more promising targets, left the game with a sprained medial collateral ligament in his right knee and could miss the next two weeks.

But after the Redskins rebounded for the victory, Turner chose to accentuate the positive.

"There were some outstanding things done in the first half," Turner said. "The thing that also struck me was, we also have a lot of work to do. When you line up with 15, 16 guys at new positions, there are some things we have to work on. But when something happened bad, our guys responded. There's a mental toughness about this team that I really like, and we're going to build on that."

Johnson completed 12 of 24 passes for 117 yards in two quarters. Frequently pressured by Buffalo defensive end Bruce Smith, he rushed some passes, intentionally overthrew others and twice was forced to scramble -- diving headfirst on one occasion. He had just three completions to wide receivers, finding the odds better dumping off to his backs.

But Johnson said he was proud of the way the first team moved the ball and had no complaints about the protection, citing instead Buffalo's prowess with defensive stunts.

"We had two long drives and should have scored touchdowns on them," Johnson said. "We never went three-and-out. We had some mishaps as far as getting certain completions. The points are going to come. I think this is a team that's going to have a dogfight week in and win out."

Against Buffalo, the Redskins' best moments came from their defense. Rookie cornerback Champ Bailey had his second interception in as many games. The defensive line played particularly well, with Marco Coleman registering a sack and tackle Dana Stubblefield helping stop the run up the middle. Buffalo managed just 62 yards rushing in 304 yards of total offense.

Buffalo made things interesting down the stretch, pulling to 20-19 on an eight-yard touchdown pass with 51 seconds left. A two-point conversion failed. Buffalo recovered the ball with an onside kick, but the Bills' final chance to score fell short.

The Redskins' opening drive fizzled at Buffalo's 43 with two incompletions to Michael Westbrook.

On their next possession, the Redskins lost Alexander. Kevin Pesak took over and grabbed a 13-yard reception that took Washington to the Buffalo 2. After Johnson threw an incompletion, running back Skip Hicks gained nothing on a carry. And Johnson, pressured from both Buffalo defensive tackles, threw another incompletion to bring up Brett Conway for a field goal attempt. The snap was bad, sending the ball tumbling downfield. Conway illegally kicked it out of bounds, and Buffalo took over at its 42.

Frustrated by Hicks's lack of production (six yards on five carries), Turner inserted Stephen Davis at tailback on the Redskins' third possession. Davis bored up the middle for a pair of first downs. But again, the drive sputtered.

Buffalo took a 3-0 lead with a 36-yard field goal by Steve Christie. The drive was helped by a 13-yard completion to Eric Moulds, who got great separation from Bailey to make the catch.

Buffalo got the ball back when Mitchell fumbled after returning the ensuing kickoff 36 yards. After getting burned a second time by Moulds, Bailey intercepted a pass intended for Andre Reed and returned it 18 yards. Again, the offense failed to convert the opportunity.

Johnson moved the ball crisply on the next series. Davis rushed 15 yards for a first down on the Buffalo 10. But Buffalo's defense forced the Redskins to settle for less than they had hoped. On third and goal from the 6, Johnson dropped back to pass and couldn't find an open receiver. He stepped back farther still as if to run, but backed into linebacker Dan Brandenburg, who sacked him.

"It was a busted route," Johnson said, "and I just scrambled around to make a play."

Conway tied it at 3 with a 32-yard field goal.

Doug Flutie entered the game for Buffalo and hit a 17-yard completion as defensive ends Ndukwe Kalu and Marco Coleman charged toward him. Coleman got his man on the next play, sacking the quarterback for a nine-yard loss.

Flutie's next series produced a 48-yard field goal that gave Buffalo a 6-3 lead early in the third quarter.

Rodney Peete, who took over for Johnson in the third quarter, showed the savvy that Turner said has earned him the backup job for now. Peete hit Westbrook with a 21-yard completion and scrambled six yards to Buffalo's 3. Davis barreled in for the touchdown, giving Washington a 10-6 lead.

Washington extended its lead on its next series with Cary Blanchard's 32-yard field goal early in the fourth quarter.

Weldon took over for Peete in the fourth quarter, but threw a costly interception. Buffalo's third-string quarterback Alex Van Pelt found tight end Bobby Collins wide open in the end zone, and the touchdown reception tied the game at 13.

Said Johnson: "When you come away with a win, you come away with positives. This is what this organization needs. Guys are excited about what's happening. We're only going to get better."