With the Yankees rotation battle coming down to the wire, left-handed rookie Jordan Montgomery could very well justify a spot on Wednesday.

Considered nothing more than a longshot coming into spring training, an uninspiring New York Yankees rotation battle has paved the way for Jordan Mongomery and on Wednesday against the Toronto Blue Jays, he’ll make his final case to travel North with the Bombers.

New York’s fourth-round pick of the 2014 MLB June Amateur Draft has struck out 13 batters in 14.2 innings of work this spring and has only let up six runs (3.68 ERA) while holding batters to a .185 batting average.

In his latest outing against a lineup full of Tampa Bay Rays’ starters, the awkward-delivering lefty struck out eight batters — including three-time All-Star Evan Longoria twice — over 4.1 innings.

But, while there is very little left for Montgomery in the minors and he’s catching the Yankee brass’ eye in camp, it’s the failure of others separating from the pack that makes it clear cut that the 6-foot-6 Montgomery should be handed the fourth or fifth spot.

In his last start against the same Rays on Sunday, right-hander Bryan Mitchell gave up three runs on six hits, walked three and struck out three as he watched his spring ERA elevate from 3.86 to 4.57.

On that same day, Chad Green pitched in a minor-league game for High-A Tampa against the Class A affiliate of the Pittsburgh Pirates and surrendered three runs on four hits over four innings.

As for other competitors, Luis Severino will get his final showcase on Thursday against the Philadelphia Phillies, Adam Warren has been assigned to the bullpen and Luis Cessa has already been assigned to minor league camp.

With that, Montgomery, who has already put his foot in the door of the competition, has a golden opportunity to blow it out of the water if he shuts down Toronto on Wednesday afternoon. Manager Joe Girardi is currently witnessing Mitchell and Green cave to the pressure, but the rookie has done the complete opposite despite the odds being against him.

“At this point, we can’t say we aren’t putting pressure on ourselves,’’ Mitchell said. “At this point in the game, you can’t not think about it. You try not to, but you still put pressure.’’

Between Double-A Trenton and Triple-A Scranton/Wilkes-Barre last season, Montgomery registered a 14-5 record featuring a 2.13 ERA and a 2.98 strikeout to walk rate in 139.1 innings. After striking out 97 batters in 19 starts at Trenton, his ERA dipped to 0.97 in his six Triple-A starts while holding the opposition to a .212 batting average.

In four starts from Aug. 7 to Aug. 25, he went 4-0 and didn’t allow a single earned in during what was a 30-inning scoreless streak.

Montgomery capped off his unbelievable year with a winning effort in the Triple-A National Championship game. He allowed just one run on six hits without a walk in five innings to secure the Governer’s Cup for the RailRiders.

The well-bred lefty is still considered a long-shot, but his dominance at the Triple-A level — at every level, for that matter — and spring showcase should make Girardi consider him one of their starting options when the roster settles to 25 men.

“We will talk about it,’’ Girardi told the New York Post of Montgomery being a serious candidate. If he dominated again on Wednesday, he might have to do more than just talk about his chances.