(L-R) Frankie Montas, Lou Trivino and Scott Effross are set...

(L-R) Frankie Montas, Lou Trivino and Scott Effross are set to join the Yankees after deals a day ahead of the trade deadline. Credit: AP

Yankees general manager Brian Cashman went 3-for-3 on his to-do list before Tuesday’s 6 p.m. trade deadline.

And there’s the possibility, club insiders said, of one more significant move to come.

As for what has been accomplished, Cashman crossed off his top three priorities.

Late Monday afternoon, he obtained righthanded starting pitcher Frankie Montas and righthanded reliever Lou Trivino from the A’s for lefthander JP Sears (who has spent some time in the big leagues this season), righthander Luis Medina, lefthander Ken Waldichuk and infielder Cooper Bowman.

Earlier, the Yankees brought in righthanded reliever Scott Effross from the Cubs for righthander Hayden Wesneski, among their better pitching prospects.

And last Wednesday, they acquired lefthanded-hitting outfielder Andrew Benintendi, who has started every game since, from the Royals.

Waldichuk is rated among the Yankees’ top pitching prospects, but Cashman thus far has avoided trading highly rated prospects Anthony Volpe, Oswald Peraza and Jasson Dominguez.

“There’s no question we added four, in their specific positions, high-caliber players,” Aaron Boone said. “So to intertwine them with our group already . . . I mean, on paper, we’re better. But I will caution that that’s just on paper. We have to go out and do it still and go out and prove that. But we definitely upped our talent these last few days.”

After both deals were announced Monday, one organizational insider said the Yankees were “working on more still, one big one that would be a big help, but nothing close yet.” It perhaps was an indication that the ultimate dream of acquiring Nationals superstar Juan Soto — though still very much a long shot — isn’t completely dead.

Montas, 4-9 but with a 3.18 ERA and 109 strikeouts in 104 2⁄3 innings in 19 starts, should give them another quality starter. That became a pronounced need when Luis Severino went down with a right lat strain July 14 (Severino started his throwing program Monday but also was transferred to the 60-day injured list; even with no setbacks, he won’t be back until September).

“He’s just a dominant starter,’’ Aaron Judge said of Montas. “Been a dominant starter for quite a while now. He’s got some ridiculous stuff. Just happy that we don’t have to face that down the road again.”

“He’s a solid No. 3,” one rival American League talent evaluator said of Montas, 29. “He’s not better than a healthy Severino, but he’s good. They needed [depth] there.”

In the bullpen as well, especially after losing Michael King to a season-ending elbow injury July 22. Though the Yankees talked up their organizational depth publicly, behind the scenes, the King injury made adding a reliever — and preferably two — a necessity rather than a desire.

That was the reason the Yankees were willing to part with Wesneski, one of the few pitchers at the higher levels of their minor-league system whom rival evaluators project as a cornerstone rotation piece.

The sidearming Effross, 28, under team control until 2028 and a pitcher in whom the Rays also were very much interested, is 1-4 but has a 2.66 ERA in 47 appearances, tied for the second-most in the big leagues. He has struck out 50 in 44 innings and held the opposition to a .220/.267/.299 slash line, including .132/.220/.245 against lefthanders.

“A good late-inning bridge,” one National League scout said of Effross, whose unusual delivery features a primary repertoire off a sinker, slider and changeup. “Definitely a different look [with the sidearm delivery] and has three solid weapons. A late bloomer, so he’s been kind of under the radar, but he checks all the boxes.”

Trivino, 30, is 1-6 with a 6.47 ERA in 39 games this year. Last year, he posted a 3.18 ERA in 71 games, striking out 67 in 73 2⁄3 innings.

“It’s a good feeling,’’ Judge said of the acquisitions and what it shows from the front office. “Kind of getting that backing from the front office that ‘hey, you guys put yourselves in position to be in a good spot going down the stretch and into the postseason and we’re going to give you a couple of pieces to boost you guys a little bit and fill some holes where we need them.’ ”

More Yankees headlines