Campion’s bid to finish West Riding County Amateur League runners-up hit the wall with a surprising 1-0 defeat at Premier Division strugglers Lepton Highlanders.
Chris Gillespie struck the only goal for the second-bottom Huddersfield hosts, opening the door for defending champions Bay Athletic to overtake Campion.
Bay moved to within two points of the Bradford club – and have five games in hand – as they followed up a 2-1 midweek victory against Halifax Irish with a 4-1 home win over Littletown.
Leaders Ovenden West Riding are also within the grasp of Bay – they would climb to within a point of top spot by winning all their matches in hand.
But Ovenden show little sign of slipping up and extended their run of consecutive league wins to 18 as Andy Bailey (2) and Damian Randall combined to sink basement side Hall Green United 3-0.
Tyersal had Aaron Heywood, Damian Rushworth and Wayne Wright on target as they beat Huddersfield YMCA 3-1 to virtually assure their top-flight status for next season.
Steeton were second best at Golcar United and suffered a 3-0 setback, with Steve Smith, Andy Briggs and Liam Rothery netting for the home side.
Hunsworth’s lead at the top of Division One seemed insurmountable just a month ago but it is now down to two points after having to settle for a 4-4 draw at home to Campion Reserves.
Lee McKeown (2), Tom Ormondroyd and an own goal for Hunsworth were cancelled out by Paul Noble, Ben O’Melia, Usmaan Hussain and another own goal.
Second-placed Lower Hopton stepped up their title challenge as Adam Stephenson netted both goals in their 2-0 win at Storthes Hall Reserves.
Ventus-Yeadon Celtic remain in third place after seeing off visitors Tingley Athletic 5-0, with Ben Leeming’s hat-trick backed up by Kyle Shah and Reece Brown.
Overthorpe SC, who were relegated at the end of last season, are making a valiant attempt to avoid suffering the humiliation of a second successive drop.
The third-bottom side have played more games than all the teams around them but boosted their chances of staying up with a 5-3 victory at fellow strugglers Steeton Reserves.
Jack Allerton led the way with a hat-trick as Ashley Hill and James Wilson also hit the target.
Salts Reserves slipped into the bottom two below Overthorpe after being held to a goalless draw at home to Wibsey.
Bradford FC, in their first season in the league, finally picked up their first Division Two point on their own ground with a 3-3 draw against Golcar United Reserves.
The new boys’ penultimate league game of the campaign saw them recover from a 2-0 interval deficit thanks to goals from James Precious (2) and Brandon Williams.