The reigning World and AMA Supercross Champion had led the shortened 12-lap, muddy 250cc Main Event from lap nine but lost out to arch rival James �Bubba� Stewart in the closing stages.

Carmichael�s RM-Z450 and Stewart�s Kawasaki clashed on the gate and took the first turn in fifth and third respectively behind holeshotter Nick Wey (Honda). But before the lap had finished, Stewart had moved into the lead and Carmichael to third.

By the half-way stage, Stewart had increased his lead to 3.8 seconds ahead of Carmichael as the pair lapped up to sixth place, then Carmichael took the awkward double jump and closed right up on the Kawasaki rider. From there on they were locked together until the Suzuki man forced ahead three laps from home.

But Stewart fought back as the pair hit backmarkers � both lapped up to third-placed Nick Wey � and Carmichael eased off for fear of crashing.

He said: �That was a real exciting race and �Bubba� deserved the win! We both rode our hardest tonight but he was prepared to give that little extra whereas I wasn�t. I had a few scary moments but I achieved my goal tonight � not to crash.

�It�s a long season and it�s better to get second than risk crashing,� added Carmichael, who continues to lead the Amp�d Mobile Supercross series by two points over Stewart.

�I don�t really enjoy mud races, I don�t know who does,� added Carmichael. �I think I�ve gotten a little older - this is my 10th season - and I�ve learned to ride in the mud. But I just don�t take the chances that I used to. What really bums me out is that the track looked so good before the rain. If it had been dry, we would have been flying.�

Meanwhile Carmichael�s team mate Ivan Tedesco struggled for most of the night. He got a great start but got tangled up with other riders in turn one and was never able to recover from a crash with Mike LaRocco on lap six.

�I got a great start and I felt comfortable and was really happy with how I was riding at first,� said Tedesco.

250 Main Event (12 laps): 1 James Stewart (Kawasaki), 2 Ricky Carmichael (Makita Suzuki), 3 Nick Wey (Honda), 4 Michael Byrne (Kawasaki), 5 Chad Reed (Yamaha), 6 Tyler Evans (Suzuki), 7 Jeff Gibson (Honda), 8 Travis Preston (Honda), 9 Ryan Clark (Honda), 10 Jason Thomas (Honda).

Championship Points (after 4 rounds): 1 Carmichael 92, 2 Stewart 90, 3 Reed 82, 4 Wey 61, 5 Byrne 58, 6 LaRocco 55, 7 Tedesco 51, 8 Fonseca 48, 9 Preston 47, 10 McGrath 44.

World Supercross Points (after 6 rounds): 1 Stewart 140, 2 Carmichael 136, 3 Reed 122, 4 Wey 98, 5 Byrne 96, 6 Tedesco 95, 7 Gibson 74, 8 Thomas 73, 9 Clark 69, 10 Evans 51.