Ramsey breaks Carmichael streak in Pontiac.

Ricky Carmichael's march towards back-to-back AMA US Supercross titles was stopped after six straight wins by team-mate Nathan Ramsey on Saturday night, as the Honda four-stroker beat the favourites in an eight-man thriller.

Nearly 59,000 fans at the Pontiac Silverdome witnessed one of the closest races of the season - if not for many seasons. For Ramsey, it marked a first career AMA EA Sports Supercross victory - and the first for Honda's four-stroke CRF450. Behind him, reigning champion Carmichael crashed, remounted and finished an amazing second, while Jeremy McGrath returned to the podium. And that meant that early season pace-setter David Vuillemin, Stephane Roncada, Ernesto Fonseca, Ezra Lusk, Tim Ferry and Sebastien Tortelli all went away 'empty-handed' after being involved at the front in some way.

After Kyle Lewis earned his first Powerade Holeshot Award by putting his Moto XXX Honda first into turn one, it was Fonseca who took up the lead with the rest of the field right in his wheeltracks.

Carmichael went down in the middle of the leading pack, being thrown from his Honda after landing awkwardly from one of the jumps. Despite stoving in the front of his helmet, RC remounted quickly and, from 19th, began a remarkable charge back through the field.

Amazingly, the accident had little effect on the group, which continued to chase Fonseca over the next few laps. Led by Tortelli, Ramsey, Lusk, Vuillemin, McGrath and Ferry all jostled for position. Frenchman Tortelli was the first to lose out, after crashing in the rhythm section, then Ramsey fell right in front of McGrath, stopping the multiple champion's progress. Both were quickly underway again, but Tortelli was not so fortunate, and dropped even further away from the group.

This left Ferry to move into the lead, with Lusk ready to swap places at any opportunity until he, too, went down in . Lusk went down in the whoop section.

With five laps to go, Ferry led the recovered Ramsey and McGrath, only to crash out in the whoops and suffer the agony of a bike that refused to restart.

Ramsey now inherited the 'hot seat' with McGrath in close attendance, but all eyes were on the return of RC, who, by now, was into third and still charging. With title rival Vuillemin and Fonseca already behind him, the champion focused on passing McGrath - something he achieved with a couple of laps to run.

Three seconds behind Ramsey with two tours to run, the crowd roared Carmichael on, but his charge required at least another lap as Ramsey held on to win a crazy race.

"I got a good start and things were happening everywhere on the track," a jubilant Ramsey told AMA reporters afterwards, "I probably wasn't the fastest guy out there tonight, but somehow I stayed out of trouble and came across the line first."

RC and MC also received hero's welcomes on the podium, but Carmichael admitted that his main aim was to extend his point lead over a certain Frenchman.

"I was just looking to see where Vuillemin was," he confessed, "I made an amateur mistake, but the fans really got their money's worth tonight. I want the championship so badly and sometimes you have to tough it out to win."

Carmichael leaves Pontiac with a 24-point lead over Vuillemin, with just three rounds remaining. McGrath now lies third in the table after overtaking Lusk. Ramsey's win only moves him into a secure sixth spot after a difficult start to the season.

Overshadowed by the 250 main was the equally surprising end to Chad Reed's domination in the 125 East series. Like Carmichael, six from six in recent races, the Australian could have graduated to the 'senior' class in support of Vuillemin's championship assault, but opted to chase a clean sweep in the 125s. A bad start on subsequent defeat by Branden Jesseman probably had him wishing he had made the jump.

Jesseman took an early lead on the Team Blimpie Suzuki after Holeshot Award winner Kelly Smith fell. Riding the race of his career, Jesseman moved into a commanding lead, while Reed fought his way through the pack.

By lap five, the Australian was right with second placed Eric Sorby, passing him on one of the jumps to leave just Jesseman in his sights. His rate of progress, despite having to pass a lot of slower bikes was remarkable, but, despite closing on the leader at almost a second a lap, the race was not quite long enough to preserve the unbeaten record.

In the final half of the last lap, Reed moved right onto Jesseman's rear wheel, but the long-time leader had just enough in hand to hold on. Forgotten in the excitement, Sorby came home a distant third.

250 Main - results:

1. Nathan Ramsey Honda
2. Ricky Carmichael Honda
3. Jeremy McGrath Yamaha
4. David Vuillemin Yamaha
5. Stephane Roncada Kawasaki
6. Ernesto Fonseca Honda
7. Ezra Lusk Kawasaki
8. Stephane Tortelli Honda
9. Nick Wey Yamaha
10. Kyle Lewis Honda

125 East Main - results:

1. Branden Jesseman Suzuki
2. Chad Reed Yamaha
3. Eric Sorby Kawasaki
4. Joshua Woods Suzuki
5. Andrew Short Suzuki
6. John Dowd KTM
7. Buddy Antunez Suzuki
8. Jeff Gibson Yamaha
9. Isaiah Johnson Suzuki
10. Michael Brown Kawasaki

250 - point standings:

1. Ricky Carmichael Honda 281 points
2. David Vuillemin Yamaha 257
3. Jeremy McGrath Yamaha 198
4. Ezra Lusk Kawasaki 195
5. Stephan Roncada Kawasaki 189
6. Nathan Ramsey Honda 179
7. Ernesto Fonseca Honda 157
8. Nicholas Wey Yamaha 138
9. Heath Voss Honda 133
10. Damon Huffman Suzuki 125

125 East - points standings:

1. Chad Reed Yamaha 172 points
2. Mike Brown Kawasaki 120
3. Branden Jesseman Suzuki 101
4. Buddy Antunez Suzuki 96
5. Steve Boniface Yamaha 91
6. John Dowd KTM 82
7. Greg Schnell Yamaha 81
8. Jeff Gibson Yamaha 78
9. Kelly Smith Honda 70
= Grant Langston KTM 70
= Larry Ward Yamaha 70