Home number one Kyle Howarth cruised into the British Final by finishing second in the semi-final at Owlerton.
The Sheffield Window Centre Tigers ace won three out of five races to end the night ahead of everyone bar maximum man Jason Garrity.
Charles Wright could not replicate his colleague’s fortunes, though, ending a troubled night on four points and well outside the coveted eight qualifying places.
Howarth had been second in his opener but got out of shape and reeled in by Josh Auty to finish third.
The Wolverhampton charger then beat Carl Wilkinson to claim three precious points in a race that finished with two riders after Wright had broken down and Danny Ayres had shed a chain in the re-run.
Wright’s battle at the back with Nathan Greaves ended in success after his rival fell in heat nine but a running total of two from three races all but ended his hopes of going through.
Howarth stayed in the mix despite coming second to Garrity in heat 12, fighting back from getting cut across early on only to see the untouchable meeting winner wind it on to maintain his unblemished record.
Wright played his part in a blockbuster in the 13th but came in last to kill any lingering hope of a late surge but Howarth seized control of his destiny by winning the tightest of tussles with British under-21 champion Robert Lambert.
It ended well enough for Wright who claimed second behind a lightning Stefan Nielsen before Howarth sealed his progress in style, steaming in between Adam Roynon and Rory Schlein to wow the crowd in the penultimate race.
Reigning British champion Craig Cook edged through in seventh, albeit with a two-point cushion over Nielsen who missed out courtesy of Dan Bewley’s success in the final race.
There were few surprises with Auty, Edward Kennett, Lambert and Schlein also progressing.
They will join the top eight from Tuesday’s second semi-final at Leicester when the showpiece is contested at Belle Vue on Monday, June 11.
BRITISH SEMI-FINAL QUALIFIERS: Jason Garrity 15, Kyle Howarth 12, Josh Auty 12,Edward Kennett 10, Robert Lambert 10, Rory Schlein 10, Craig Cook 9, Dan Bewley 9.
NON-QUALIFIERS: Stefan Nielsen 7, Carl Wilkinson 5, Charles Wright 4, Nathan Greaves 4, Adam Roynon 4, Max Clegg 3, Zach Wajtknecht 3, Danny Ayres 2.