Brandon Kintzler, whom the Nationals acquired just before Monday’s trade deadline, converted 28 of 32 save chances with Minnesota this season and was an AL all-star. (Jayne Kamin-Oncea/USA Today Sports)

Baseball has seen few deadline duels like the one between the Washington Nationals and Los Angeles Dodgers as the last seconds ticked off before the 4 p.m. trade deadline Monday. A classic front-office and ownership rivalry is fast developing here. Or rather, one of long standing is coming to a head.

If the Nats think it’s their destiny to win Washington’s first World Series in 93 years, then their front office, built by former team president Stan Kasten, will have to go directly through L.A. and the current Dodgers front office that was also built by Kasten after he left D.C., miffed at a lack of authority under the Lerners.

Monday was another tit-for-tat duel, just like their five-game, down-to-the-last-out division series struggle last October, won by the Dodgers, and their battle to sign free agent Kenley Jansen last winter, with an offer from the Nationals of $85 million beaten by a slightly lower Dodgers offer.

On Monday, down to the last tick-tocks, the Nats became a favorite to reach the National League Championship Series by trading for all-star closer Brandon Kintzler of the Minnesota Twins. Then, perhaps a minute later, L.A. spectacularly trumped the Nats and made itself the favorite to win such an NLCS showdown by trading for Yu Darvish, the No. 1 strikeout-rate starter of the last five years.

In those final instants, the Nats got what they needed, although perhaps not quite what they have wanted for the past eight months.

The Dodgers, who have the majors’ best record at 74-31, picked up starter Yu Darvish from the Rangers at Monday’s deadline. (Richard W. Rodriguez/Associated Press)

[Nationals trade for Twins closer Brandon Kintzler at deadline]

Who says, after eight months of searching, the Nats couldn’t come up with a closer with an all-star résumé? As a rental player, free after 2017, Kintzler also came cheap in salary (barely $1 million for the last two months) and prospects. Because Kintzler’s stay will probably be short, Ryan Madson and Sean Doolittle, under team control through 2018, won’t feel that their bullpen futures are blocked.

By the standards of his job description, the 6-foot, 190-pound right-hander, who turns 33 on Tuesday, is underwhelming but efficient. Kintzler depends on control, strikes out few men, seldom allows a walk or home run and is a very nice though unspectacular addition to the Nats, thank you. He’s never been in the playoffs. His 2.98 ERA the last two years after a switch to relief is exactly who he is — steady and useful. a flexible complement to the recently added Madson and Doolittle from the A’s.

Rizzo said the deal was finalized “extremely close” to the drop-dead minute. As for Kintzler’s role, the Nats have two months to find out how he fits at the back end with recently added Madson, 36, who has looked exceptional in the eighth inning, throwing harder than he ever has in his life, up to 99 mph, and Doolittle, who has battled uncharacteristic wildness as the closer but surmounted the problem with 90 percent fastball aggressiveness.

In this context, Kintzler isn’t a dominant playoff game-charger but an odds-improver, a key to what could evolve into a flexible mix-and-match Nats bullpen to get the last six to 12 outs. With lefty Enny Romero hitting 101 mph and young Koda Glover presumably returning from injury, the Nats could end up with a deep corps, balanced between lefties and righties, that’s well-suited to October bullpen battles that start in the sixth inning. Even if the Nats lack a superstar, humiliate-’em closer.

Whatever the roles, in two weeks the Nats have gone from having a horrific bullpen, the worst in MLB, to one that has no excuse not to be at least good. For a matter of seconds, the gap between the excellent but injured Nats, playing .606 ball, and the sun-surface-hot, yet even more injured Dodgers, who are playing ridiculous .702 baseball, become slightly narrower.

The Nats’ chances, even against this L.A. quake that seems to unearth some new farm-system prodigy every month, got marginally better. After all, L.A. ace Clayton Kershaw is out for four to six weeks with back pain similar to what cost him 10 starts in 2016. Lefty Alex Wood, 13-2, has been rocked his last two times out. Maybe the Dodgers aren’t, as some have said, “the Warriors of baseball.”

Then in a blink, as L.A. president and part-owner Kasten watched the clock and remembered his within-the-last-minute negotiations to sign Stephen Strasburg and Bryce Harper for the Nats, the Dodgers swung a monster traded for the lavishly gifted, sometimes inconsistent Darvish.

[Dodgers were already MLB’s superteam — and then they got Yu Darvish]

“Getting the Darvish deal done was definitely Strasburg-and-Harper-ish,” said Kasten on Monday, chuckling to recall those negotiations in 2010 and 2011 when he and current Nats GM Mike Rizzo doubled-teamed super-agent Scott Boras to hammer out record-high contracts to amateurs for the two current Nats stars.

“But we got it done. It just took a couple of minutes [at the end],” said Kasten who has coveted Darvish for a decade, longing to find a way to get him in his Nats days long before most in the United States had heard of Yu’s exploits in Asia. “And we didn’t have to touch the top of our farm system.”

The Dodgers also added two serviceable left-handed relievers in the closing hour before the deadline after a possible deal with the Orioles for Zach Britton fell through late, perhaps when the O’s front office went to ownership for approval.

For the Nats, no Britton on the West Coast is just fine. Darvish is more than enough of a problem. He can be a dervish who makes you look helpless with five kinds of breaking balls and a lightning fastball, too. Or as he did in the 2016 playoffs, he can give up four homers in five innings and lose to Toronto’s J.A. Happ.

Since 2012, when Darvish arrived from Japan, the top three pitchers in baseball in strikeouts-per-nine-innings are Darvish (11.0), Washington’s Max Scherzer (10.9) and Strasburg (10.5) with L.A.’s Kershaw sixth (10.2).

By 4:02 p.m. on Monday, half of baseball was fantasizing about a playoff rematch between the Dodgers and Nats. But this October, such a showdown would more likely be in the NLCS, with a trip to the World Series at stake, not just a division series, like the Dodgers’ Game 5 win in 2016 with Kershaw saving the last game in relief.

If the makeshift Kintzler-Madson-Doolittle solution ends with the Nats in the World Series, or at least a long classic battle with the Dodgers, then much will be forgiven concerning this year’s bullpen circus. But if they don’t, it probably won’t.

Then, it will be remembered that the Nats’ front office provided ownership with a Plan B after Jansen and Mark Melancon were off that table. The Nats could have, at manageable cost in dollars and prospects, gotten both dependable closer David Robertson of the Chicago White Sox and risky back-from-surgery Greg Holland, who now leads MLB in saves, as their back-end of the ’pen. Ownership declined.

Something better would arrive, internally or at the trade by deadline. Except that it didn’t happen. Now, at the last minute, the Nats have added their third good reliever of July. Will that be “good” enough on an October stage where recent playoff history says that “great” is often demanded from bullpens?

This fall, it may be the Dodgers who provide the litmus test.

For more by Thomas Boswell, visit washingtonpost.com/boswell.