Aberdeen, South Dakota veteran Curt Gelling, and Trent Grager led the field to the initial green of the main event.
Gelling took the point through turns one and two at the start, and brought former Jamestown native Ryan Mikkelson with him, as the latter moved into the runner-up spot at the completion of the first circuit.
Seng then moved past Grager into third, as Cole Schill rounded out the top five in the No. 44 Mid Ag Dispatch MB Custom through two laps.
The first caution of the race came on the fourth lap for a spinner in turn one, setting up the first Delaware double-file restart of the 25 lap event.
Mikkelson chose to go low for the restart, as Gelling resumed the race as the leader.
The lead trio went three-wide for the lead at the start/finish line at the end of the fourth lap, with Gelling barely edging out Seng and Mikkelson to keep the lead.
Seng took the top spot on the exit of turn two on the following lap, however, and began to build a lead shortly thereafter.
The second caution of the race came on lap six, this time with Seng as the leader on the ensuing double-file restart.
Dustin Strand (71) and Brody Troftgruben (14) will be separated by just 60 points with one race remaining.
Speedway Shots photo.
As Cole Schill began to pull even with Gelling for the final spot on the podium, the caution lights came on for the third time, this time with six laps complete. The field was brought to a halt, however, as the two car pileup was cleaned up in turn two.
When action resumed, Seng continued to pace the field, as Mikkelson took second from Gelling again. Schill then resumed his attack for the third spot, taking the position from Gelling at the end of lap ten.
At the halfway point, Seng had built an advantage of nearly a full straightaway, as Mikkelson and Schill battled for second. Seng began working lapped traffic as the race neared the ten to go mark.
Two final caution periods with four laps remaining gave Schill and Mikkelson one last shot to chase down Seng for the victory.
Mikkelson switched from low to high between the two restarts, eventually playing in his favor, as he was able to keep second, as Seng continued on to victory. Schill was third, with Aberdeen's Josh Skorczewski and Gelling rounding out the top five respectively.
Dustin Strand was unable to start the main event in the No. 71 Carr's Grain Service Millenium SRT, thus closing the points gap between him and Brody Troftgruben and his No. 14 Applegren Construction Rocket. The pair will be separated by 60 points heading into the tour championship at the 'Prelude to the Johnny' at River Cities on September 10th.
Seng is third, with Troy Schill fourth in the No. 11 Todd's Electric MB Custom, and Blake Anderson rounding out the top five in the No. 9A Pro Mark Services Rocket.
Jeff Hapala moved up all the way to sixth after a trio of top ten finishes last week in the No. 16S City Parcel Delivery MasterSbilt. Steve Anderson is seventh with the No. 9 Spicer Trucking MB Custom, with Dan Dowling eighth in the No. 02 Knickerbocker Liquor Locker Bloomquist. Ryan Corbett, driver of the No. C4 Jess Rice Crary Realty MasterSbilt, and rookie Kreig Kasin and the Kasin Racing No. 47 round out the current top ten.