Chase Sexton's championship lead cut to just seven points.
Three-time national champion Eli Tomac has become the first rider to win two outdoor rounds this year, after a strong 1-1 performance at the RedBud round of the Lucas Oil Pro Motocross Championship.
After qualifying fastest earlier in the day, the Monster Energy Star Yamaha Racing rider took a wire-to-wire win in the opening 450MX moto.
He began with a big holeshot from Joey Savatgy (Monster Energy Kawasaki) and Justin Barcia (TLD Red Bull GasGas), and he quickly put distance between himself and the pack.
Monster Energy Kawasaki’s Jason Anderson went down in the first turn and remounted at the rear of the field.
Ken Roczen worked his way through traffic up to third over the opening couple of laps, but would succumb to pressure from his Team Honda HRC team-mate, Chase Sexton, as the laps wore down.
Up front, Tomac continued his charge, building a comfortable seven-second lead by the time he crossed the finish-line.
Sexton would make a late move on Savagty to take second from the Kawasaki racer, as Roczen and Chrisian Craig (Monster Energy Star Yamaha Racing) rounded out the top five.
Ryan Dungey (Red Bull KTM) came home in sixth, ahead of Anderson, who put in a remarkable charge from the rear of the field to P7.
Barcia, Aaron Plessinger (Red Bull KTM) and Marshall Weltin (Twisted Tea HEP Motorsports Suzuki).
Tomac’s dominance continued into the second moto, capping off a perfect July 4 weekend.
Justin Barcia secured the holeshot, followed closely by Tomac and Roczen, but it only took three laps for Roczen, then Tomac to clear the TLD Red Bull GasGas rider.
Tomac slowly whittled down Roczen’s two-second lead, while an intense four-rider battle broke out between Barcia, Anderson, Dungey and Sexton.
After getting momentarily held up in an Anderson crash, Sexton went into damage control, quickly picking off riders as he charged up to third.
Ahead of him, Tomac took advantage of a slight mistake by Roczen to take over the race lead with 15 minutes left on the clock.
From there Roczen faded dramatically, allowing multiple riders past him, including Sexton. T
here was no stopping Tomac, though, as he claimed an eight-second victory from Sexton, with Barcia completing the podium.
Anderson would finish fourth and Dungey a hard-fought fifth. P6 to P10 were filled by Craig, Roczen, Plessinger, Savatgy and Garrett Marchbanks (Muc-Off FXR ClubMX Yamaha).
Sexton still remains at the top of the points standings, but his lead over Tomac has been trimmed to just seven points. Roczen remains third, a further 23 points back.
The sixth round of the Pro Motocross Championship will be held at Southwick on Saturday, 9 July.