Goals from Stuart Beavon and Joel Grant were not enough for Wycombe as Robbie Simpson's 90th-minute penalty earned Oldham a 2-2 draw.
Filipe Morais gave the visitors the lead in the 14th minute, but Beavon ensured the sides went into the break level with his 23rd goal of the season.
Substitute Joel Grant thought he had secured all three points 12 minutes from time and the Wanderers had a chance to seal victory, but Grant Basey missed from the penalty spot.
However, there was a late twist as Marvin McCoy brought down Simpson in the area and the striker held his nerve to deny the Blues.
Marvin McCoy blazed a shot wide early on, before Oldham's Robbie Simpson came close with a powerful left-footed effort from the edge of the area.
The Latics took the lead in the 14th minute when Filipe Morais was allowed far too much space on the edge of the area and he rifled home via the right-hand post.
Simpson had a free-kick deflected just wide, but Wycombe came to life on the half-hour when Matt Bloomfield found Anthony McNamee and his flighted cross almost gave Stuart Lewis a tap-in at the far post.
Wanderers kept the momentum going and got the equaliser four minutes later when Stuart Beavon ended his three-game scoring drought.
Oldham keeper Dean Bouzanis had looked favourite to get to Ben Strevens' through-ball, but Beavon nipped in and fired home.
Shefki Kuqi thought he had restored the Latics' lead in first-half injury-time, but his strike was ruled out for offside.
Wycombe started the second half brightly and Beavon's low effort from the edge of the area was turned away by Bouzanis, who then kept out Strevens.
Morais had a shot from the edge of the area, but Bull comfortably saved and Leon Johnson was then denied by Bouzanis following Bloomfield's dangerous free-kick.
Gary Doherty just wide from a corner as the Wanderers went in search of a second and Bouzanis did superbly well to parry Grant Basey's free-kick around the post.
Substitute Joel Grant gave Wycombe the lead they deserved 12 minutes from time when the ball broke to him 30 yards out from goal and he skipped past a defender before finding the bottom right corner from 10 yards.
Basey had the chance to wrap up the points seven minutes from time after Craig Eastmond had been brought down in the area, but he put his penalty wide of the left post, ensuring a tense finale.
Substitute Harry Bunn had a shot blocked by Leon Johnson before Furman fired at Bull, but Oldham were handed a lifeline in the 90th minute when McCoy bundled over Simpson in the area.
Simpson took the penalty himself and sent Bull the wrong way to deny Wycombe at the death.
Wanderers: Bull, McCoy, Basey, Winfield (c) (Johnson 35), Doherty, Eastmond, Lewis, Bloomfield, McNamee (Grant 58), Strevens, Beavon.
Subs not used: Foster, Ainsworth, McClure.
Goals: Beavon (34), Grant (78).
Oldham: Bouzanis, Lee, Diallo, Brown, Tarkowski, Morais(Bunn 85), Furman, M'Changama, Robbie Simpson, Kuqi (Marsh-Brown 71), Tounkara.
Subs not used: Luke Simpson, Winchester, Belezika.
Goals: Morais (14), Robbie Simpson (90 pen)