The results mean Thistle stay second, three points behind Port Hill with a game in hand, and United are third, six points behind Thistle.
Both Thistle and United have two games to play, the second of which is against each other at Childers Road Reserve.
Port Hill beat Taradale 4-1 at Taradale on Saturday and have a goal difference two goals better than Thistle's.
For their last game, Port Hill are at home to Maycenvale. On Saturday's form, Maycenvale could do Thistle a favour and beat the league leaders.
Then it would be up to Gisborne Vehicle Testing Thistle to get the results they need against Napier City Rovers Seconds this Saturday and Gisborne United on September 12.
The Jags will have to work hard to stay “in the moment” because at this stage of the season it's easy to get carried away with all the permutations of what could happen.
If they keep winning and don't let up on the goalscoring front — in case it comes down to goal difference — they can't go far wrong.
On Saturday, Thistle took a while to get into their work.
Maycenvale gave them a nudge in the 23rd minute when Isaiah Andrews sent in a right-wing cross from about the midway point of Thistle's half. It found Adam Woon at the far post, and his header was just wide.
Three minutes later, Maycenvale went a goal up. Ameti Seneta, a tenacious midfielder who popped up wherever he was needed, received the ball just outside the Thistle penalty area, near the right-hand corner of the box. He laid the ball off three metres infield to attacking midfielder Dylan Cozens, who took one touch to push it clear of the marking defender and then hit a right-footed shot low and hard into the bottom right-hand corner.
Thistle's play assumed more urgency. In the 32nd minute, left-winger Justo Rodriguez got to the byline and cut the ball back towards the Jags' oncoming strikers. Seventeen-year-old Maycenvale goalkeeper Hamish Long dived full-length out towards the onrushing forwards to gather the ball. It was one of many saves that kept Maycenvale in the game.
In the 34th, goalscorer Cozens gave away a free-kick for a reckless challenge, 25 metres out.
Thistle centreback Ander Batarrita used the wind and the spin he put on the ball to curl it around the defensive wall and just inside the left-hand upright. Long did well to get his hands to the ball, colliding with the post in his vain attempt to keep it out.
Maycenvale withstood almost constant pressure for the rest of the first half.
In the 37th, Rodriguez squared the ball across the front of the penalty area to central midfielder Agustin Ventre, whose 20-metre first-time shot was just over.
In the 40th, a Tomek Frooms left-wing corner was headed just wide by striker Davie Ure.
In the 42nd it was Ure again, shooting from the right. Long tipped the ball on to the near post and it ricocheted across the goal and away for a corner.
The pattern continued into the second half. Thistle built play well from the back, whether from goalkeeper Mark Baple, fullbacks Emerson Araya and Kuba Jerabek or centrebacks Daniel Venema and Batarrita.
Brandon Josling, on the right, and Rodriguez had big jobs on the flanks, because while they were foils for striker Ure, they had to try to nip in the bud any Maycenvale attacks down the wings.
Nick Land and Ventre were a good pairing in the centre of midfield. Both play good football, work hard and can get stuck in. The solid base they created allowed Frooms the freedom to create a bit of mayhem from just behind the forward line.
And Ure kept looking for the opening among a forest of Maycenvale defenders.
Centreback Matt Ebbett and leftback (and player of the day) Jacob Rosandich were outstanding in a gritty Maycenvale backline well supported by midfielders Adam Woon, Ben Foxall, Cozens and Seneta. The back four quickly became the back eight when Thistle attacked.
Maycenvale were dangerous on the counter-attack. Ashley Skinner and Matt Goodwin caused Thistle problems when the ball was delivered quickly down the middle. Late runs from the Maycenvale midfield meant the Jags had to backtrack quickly when attacks broke down.
Land's 35-metre shot that hit the bar in the 55th minute was the closest Thistle came to scoring until the 80th, when they got their second goal.
Sixteen-year-old Campion College student Andre Riley had come on in the 72nd minute for Josling.
Riley's speed took him past a defender and into the penalty area, which is where he landed after his foot was clipped.
Referee Chris Niven ruled contact occurred just outside the area, so Batarrita took the free-kick. This time a defender deflected the ball, but only as far as Rodriguez, who guided his header past the keeper to make it 2-1.
In the 82nd minute, Ure was rewarded for his efforts. Getting clear on the right, he waited until the keeper committed himself and then found the only path for his shot that hadn't been blocked off — between the keeper's legs . . . 3-1.
The late autumn sunshine took its toll, and both sides called on fresh legs.
Charlie Morris went on for Ventre in the 74th minute, at which time Maycenvale put on Sam Ebbett for Cozens. Five minutes from the end, Maycenvale also put on Caleb Heard for Adam Woon.
Thistle's two quick goals would have killed off many teams, but not Maycenvale.
In the 87th minute, Goodwin broke wide on the left and his shot across the goal was begging for a tap-in.
A minute later, he worked his way clear in the penalty area and guided his shot just inside the right-hand post . . . 3-2.
Thistle endured a nervy couple of minutes to the final whistle but deserved their win.
Coach Garrett Blair praised the free-kick of Batarrita and the finishing behind Ure's goal, and said it was easy to see how Maycenvale had achieved positive results against good teams.
Maycenvale coach Paul Woon said his team had started the second round in last place but since then had won four games and lost two.
“We have Port Hill next week,” he said.
“If anyone wants this championship, they are going to have to win it.
“We will give it everything.”
Woon said the signing of Foxall and Skinner had been big factors in Maycenvale's improvement, and next year the aim would be to win the title.
Paul Woon, himself, had only returned to the club this year.
“I was one of the original juniors when Maycenvale started,” he said.
“The last time I came to Thistle with Maycenvale I was playing . . . in the '90s.”
In Hastings on Saturday, Gisborne United had trouble shaking off a feisty Western Rangers side before pulling away late in the second half.
Dane Thompson, back in midfield with the return to the side of sweeper Kieran Higham, opened the scoring in the 11th minute.
Thompson climbed high to strongly head home a Malcolm Marfell left-wing corner.
Rangers equalised five minutes later in spectacular fashion. United cleared a cross, but at the edge of the penalty area the ball fell to a Rangers player who powerfully volleyed it into the top-left corner of the goal.
United regained the lead in the 30th minute, when Campbell Hall sent in a cross from the right wing. Marfell made a near-post run and got a headed flick that took the ball in at the far post to give United a 2-1 halftime lead.
Rangers equalised again five minutes after the break. Goalkeeper Seth Piper got a hand to a cross but could not hold it, and a Rangers player was on hand to force the ball over the line.
Striker Josh Adams broke the deadlock in the 78th minute when he stepped up to a free-kick just outside the box and belted it into the top-left corner of the goal.
Rangers were still getting over that when they conceded a penalty in the 82nd minute and holding midfielder Kieran Venema coolly made it 4-2.
Marfell was named player of the day for outstanding performances at left wing-back and in midfield.
Jarom Brouwer was unavailable for this game but Josh Harris looked to have got over the niggling groin injury that had been troubling him for much of the season. He gave a non-stop display of midfield endeavour.
Jean-Charles Fixot, who hails from Brittany in France, played well as a central defender alongside Mal Scammell and Higham.
United coach Corey Adams said Venema was a powerful presence.
“Kieran had a good physical game,” Adams said.
“They were a physical side and we needed to graft for the win. We tried to play football, but the surface was rough.”
Attacking player Campbell Hall got in just over half a game, a sore hamstring curtailing his part in proceedings.
Sam Royston came on for Josh Adams, and in eight minutes of play hit the crossbar twice.
United's next game is against Taradale at Harry Barker Reserve on Saturday, when the Challenge Cup will be on the line. If United win, they will keep the cup for summer and — for the third year in a row — be able to have their name inscribed on it as year-end holders.