OAKLAND, California (Ticker) -- The Oakland Athletics continue to give a new meaning to the word "dramatic."

After being the first team in 26 years to squander an 11-run lead, pinch hitter Scott Hatteberg's home run with one out in the ninth inning gave the Athletics a 12-11 triumph over the Kansas City Royals.

It was Oakland's third consecutive walk-off win and 20th straight victory - the longest success streak in 67 years.

Oakland erupted for six runs in the first inning, extended its lead to 11-0 after three frames and seemingly was well on its way to breaking the American League record for consecutive wins.

But Kansas City did the unthinkable, scoring five times in the fourth and eighth innings before knotting the contest with two outs in the ninth against closer Billy Koch.

The last team that failed to hold an 11-run lead was the Chicago Cubs, who ultimately dropped an 18-16 decision to Philadelphia on April 17, 1976.

After Miguel Tejada launched a three-run walk-off homer on Sunday and slapped the game-winning single in the bottom of the ninth Monday, Oakland was in search of a new hero. With one out and rookie Eric Byrnes due up, manager Art Howe called upon Hatteberg, who lined a 1-0 offering from Jason Grimsley (3-6) into the seats in right-center field.

"Grimsley throws so hard and he throws that sinker," Hatteberg said. "All I thought was 'I want to make contact, try and get a double and get in scoring position.' I get a ball and then this pitch is thrown and I hit it. At first, I didn't think it was going to go out, but it did. This is like an outer-body experience for me right now."

It was the fifth walk-off homer of the season for Oakland and third by a pinch hitter.

"This wasn't one of our normal type of wins," Oakland manager Art Howe said. "It took everything we could muster to get it done, but we did. I'm glad we had an off day yesterday. If they were back-to-back-to-back, they would have had to cart me out on something. I know it was a record-breaker, but I don't want to watch this one on film."

The win extended the Athletics' winning streak to 20 games, the third-longest in major league history since 1900. Oakland is one win away from tying the 1935 Cubs and six away from the 1916 New York Giants, who captured 26 in a row with a tie along the way.

"This win streak is like a fairy tale," Hatteberg said. "A huge crowd cheering you every step of the way. The win streak just keeps bonding us together. We're getting so tight in here."

"Yes, it is a fairy tale," Koch added. "There aren't many words that can describe this. It's just so unbelievable."

The game was played in front of a crowd of 55,528, the largest ever to attend a regular season game at Network Associates Coliseum.

"The atmosphere here with the crowd made it like a playoff game," Kansas City interim manager Tony Pena said. "And we played it like it was one. By the end of the game, everyone on the team was standing on the top step yelling and screaming."

Koch (9-2) gained his third win in as many games despite allowing a run and two hits in one inning for his sixth blown save.

"I'm really upset with myself for giving up that run and costing Timmy (Hudson) the win," Koch said. "I can live with the blown save. (Kansas City) just won't buckle under. It was amazing. It was a totally fun game out there, even though we almost lost it. You have to say they never gave up and never quit. They're a lot better team than people believe they are."

The Athletics jumped all over Kansas City starter Paul Byrd, who surrendered six runs and six hits in just one inning, his shortest outing of the season. Ray Durham opened the first with a triple and scored on a single by John Mabry, who went 2-for-5 to improve his lifetime average against the Royals to .383 (23-for-60).

Eric Chavez plated Mabry with a single and Tejada, who was hit by a pitch, scored when left fielder Raul Ibanez misplayed the ball for an error. Jermaine Dye followed with an RBI triple and Mark Ellis lifted a sacrifice fly before Ramon Hernandez smacked a run-scoring double to deep right-center to cap the rally.

"I thought they had an insurmountable lead," Byrd said. "It's sad I dropped the ball by giving up all those runs out there. I lost the game for us tonight. They didn't lose out there, I lost. All I needed to get out of that inning was a screaming line drive to someone to break their momentum, but I didn't get one. My game is location and I didn't have it. Without that, my variety of pitches didn't matter."

"Paul just didn't have it tonight, so I took him out after the first because I wasn't going to let him die out there," Pena said.

Mabry belted a solo homer off reliever Darrell May in the second, his first off a lefthander since 1996, to give Oakland a 7-0 bulge.

The Athletics, who improved to a major league-best 38-13 since the All-Star break, were at it again in the third, plating four runs to open an eleven-run cushion.

David Justice hit a leadoff double and scored on Ellis' single. After Terrence Long walked, Hernandez stroked an RBI double to deep right-center to plate Ellis. Two outs later, Chavez, who extended his hitting streak to 12 games in the first, slapped a two-run single to right-center for an 11-0 advantage.

Kansas City chipped away in the fourth, scoring five times to cut the deficit to six runs.

With the bases loaded and one out, Dee Brown hit a two-run single and Neifi Perez followed with an RBI single to center. After Luis Ordaz flied out, Michael Tucker stroked a two-run double to left off Oakland starter Hudson.

Hudson, who has not lost in eight starts since July 24, yielded five runs - two earned - and 11 hits in 6 2/3 innings, striking out six without a walk.

In the eighth, the Royals drew within 11-10 against the Oakland bullpen. Brent Mayne and Brown opened the frame with walks off righthanded sidearmer Chad Bradford. Perez reached on an infield single to load the bases before Tejada made a fielding blunder that nearly cost his team the game.

Ordaz hit a bouncer to the Oakland shortstop and instead of getting the sure out at third, Tejada made a weak throw to the plate in an attempt to get Mayne, who scored Kansas City's sixth run.

Lefthander Ricardo Rincon entered the contest and fanned Tucker before getting Carlos Beltran to hit a fly ball for what would have been the third out. Instead, Brown scored on the sacrifice fly and Mike Sweeney followed with a three-run homer off Jeff Tam to cut the Royals' deficit to 11-10.

"At first, I thought I had hit it foul, that the ball would break and go foul," Sweeney said. "But the wind kept it fair. I thought after that first inning there was no way we could come back. We'd get some runs, but we wouldn't come back."

The home run was the first allowed by Tam since May 26, 2001, a span of 79 appearances.

Joe Randa opened the ninth with a single off Koch and was lifted for pinch runner Kit Pellow, who moved to second on a sacrifice. After Brown struck out, pinch hitter Luis Alicea dropped a 1-2 pinch into left field for a single and Pellow easily beat Byrnes' throw to knot the game.

"It was scary," Hatteberg said. "They kept coming back. We were watching them and they weren't giving up. We were very lucky tonight and we learned a valuable lesson out of this, I hope."

"It was a great ballgame," Pena said. "They came out swinging and jumped out to that early lead. But my boys didn't quit, they kept their heads in the game and were able to tie it up. Sometimes when you lose, you actually win and that's what happened tonight. We held our own against the best team in the majors and that goes a long way."

The victory was the 10th in a row at home for the Athletics, tying the second-longest streak in Oakland history, and improved their record to 78-0 when leading after eight innings.

Oakland finished the season series with an 8-1 record against the Royals and have won 22 of the 30 contests between the teams in the last three years.