There was nothing pretty about the first half, but there was plenty to admire in the way the two sides defended as though their lives depended on it, as, in Super League terms, they may.
Oldham made their breakthrough early, Afi Leuila slipping the ball to Atcheson, who seemed hemmed in on the right wing. The full-back took the low level route, diving through the tackles of Jason Flowers and Andrew Schick to touchdown, Luke Goodwin kicking the conversion from the touchline.
Oldham's tackling then held up well as Castlefield tried to get back on terms, keeping their try line intact and conceding only a penalty, landed by Lee Crooks after they had strayed offside.
Castleford themselves spent time under siege, a combination of their determination and Oldham's handling errors keeping the home side out, although both Leuila and Matt Munro went close to getting the ball over the whitewash.
It was Oldham's turn to take the strain after the break, with Castleford piling on the pressure.
It looked as though they had lifted the siege when Darren Abram intercepted and raced away, but he was ruled offside and not only brought back but sin-binned into the bargain, making his side's defensive chore even more onerous.
They had to crack eventually and they did when Shick took a pass from Richard Russell to charge down the left flank for the equalising try.
Three minutes later, with Abram still off the field, Lee Harland made another run through an increasingly weary Oldham line, flinging out a one-handed pass for Jason Roach to finish the move.
Crooks missed his conversion but obliged with a penalty after two Oldham players had stolen the ball from Danny Orr.
Oldham hit back with everything they possessed and had good chances in the last six minutes when John Clark was driven back after getting over the try-line, and when Howard Hill gave the ball away in a promising position.
In the last minute, when all seemed lost, Atcheson struck again diving under the sticks to leave Goodwin the kick to tie the game and give each side a point towards their battle against relegation.
Oldham: Atcheson; Myler, Abram, Fawcett, Leuila; Maloney, Crompton; Gildart, Stephenson, Temu, Davidson, Munro, Goodwin. Substitutes used: Clark, Hill, Lord, Topping.
Castleford: Flowers; Roach, Critchley, Vowles, Chapman; Steadman, Ford; Sampson, Russell, Crooks, Tonks, Schick, Cuuta. Substitutes used: Orr, Harland, Sykes, Smith.
Referee: R Connolly (Wigan).
Iestyn Harris and Terry Newton, both once of Warrington, added to the problems of their former club by orchestrating a 50-12 Leeds victory over Wire in front of another 10,000 Headingley crowd. Harris kicked seven goals from eight attempts and scored a try, bringing up his 600th career point in the process, and Newton was man of the match as Leeds strengthened their hold on second place before the Super League's three-week break.Reuse content