Runners-up Heavy Equipment Services United (3) piled on the goals in their last match of the season, beating Campion College 13-6.
United needed Thistle to lose if they were to overhaul their rivals, but the Jags were having none of it.
In the Championship Division 2 game, runners-up Vintage started the game three points behind Bohemians, with a goal difference 10 goals worse. They needed to win by five to pinch the title on the last day.
Curtain-raiser to this game was a crucial Championship game between Division 1 frontrunners Carpet Court Thistle Massive and Heavy Equipment Services United.
Thistle Massive won the match 5-2 to give them a huge boost heading into the last three rounds of the competition.
Thistle have 19 points from seven games (since the Championship was split into first and second divisions); United have 16.
Massive’s last three games are against Sunshine Brewery Wainui Sharks, Coates Associates Wainui Demons (both at Wainui) and Gisborne Boys’ High School (1) at Childers Road Reserve.
Boys’ High have already upset United 4-2 in the Bailey Cup final, and neither Wainui team can be taken for granted.
United’s last three games are against Demons at Harry Barker Reserve, Gisborne Boys’ High School (1) at the rectory ground and Lytton High School at Harry Barker Reserve.
United still have a chance of the title if Massive lose a game or draw all three, but United must win their games convincingly. As things stand, Massive’s goal difference is 13 goals better.
On Saturday, Thistle Massive led 2-0 through goals to right-winger Kane Stirton and striker Nic Somerton, but United striker and player-coach Stu Cranswick pulled one back just before halftime.
Five minutes into the second half, Thistle central midfielder Max Mika made space with a good turn and shot from the edge of the penalty area to make it 3-1.
Cranswick struck again to make it 3-2.
Midway through the second half, Kane Stirton limped off to be replaced by Ander Batarrita, one of two first-team players brought into the squad to fill the gaps left by injuries; the other was Kuba Jerabek, who plays leftback for the first team but ventured forward more in this game.
Within minutes, Batarrita made an impact, scoring from well outside the area.
A little later, he started the move that made the game safe for Thistle, passing from the right flank to Matt Smith, who moved the ball on to midfielder Craig Stirton on the left, and he tucked it away.
United kept battling, but Thistle were not going to lose it from there.
Craig Stirton was Thistle’s man of the match for an industrious and canny display in the middle of the park. The Jags were also well served by Chris Spurr, who’s had a great season at centreback, rightback Daniel Contreras, central midfielders Reece Brew, Phill Gill and Mika, and left-winger Matt Smith, enjoying a late-career flowering in attack.
For United, Al Knight performed wonders in goal, parrying a couple of second-half thunderbolts, one an outstanding volley from Fletcher Stewart-Hill from an acute angle and the other a sweetly struck drive from Somerton.
Cranswick was dangerous up front, as ever, and midfielders Craig Christophers and Aaron Graham never stopped trying to find the chinks in Thistle’s armour.
Centreback Jonathan Purcell, Graham and Cranswick all had first-team-squad duty in the Federation Cup final to follow at Harry Barker Reserve, but they showed no desire to save something for later. They left it all on the pitch.
In the later game, it was clear by halftime that Bohemians were in a title-winning frame of mind. They went 1-0 up in the 10th minute when striker Gary Cunningham finished Stevie White’s right-wing cross.
Thistle Vintage struck back with a Dave Watson drive from the edge of the penalty area and then a deflected Neil Hansen shot from outside the area.
Bohemians central midfielder Hayden Donnelly brought it back to 2-2 with a 20-metre effort 10 minutes before the break, and the second half was goalless.
For the Bohs, leftback Josh Blair, centreback Chris Cockburn, midfielders Matanuku Mahuika, Matt Sowerby and Donnelly, and wingers Jonte Lexmond and White were outstanding.
For Vintage, keeper Charlie Kapene, defenders Roger Faber, Geoff Griffin and Toby Pickering, midfielders David Raggett, Watson and Hansen, left winger Luis Lobon and striker Andre Riley stood out.
Referee Nigel Mead, 74, with 51 seasons of refereeing behind him, had a stormer. The knee injury that ended his playing career did refereeing a huge favour.