WASHINGTON — The Washington Commanders might plan to build through the draft, but they made a splash ahead of Tuesday’s NFL trade deadline, acquiring four-time Pro Bowl cornerback Marshon Lattimore from the New Orleans Saints. New Orleans will also send over a 2025 fifth-round draft pick in exchange for Washington’s own 2025 third-round pick, plus its 2025 fourth- and sixth-round picks.

Lattimore instantly upgrades the Commanders’ secondary and adds more star power to a team that has quickly transformed into a contender with rookie quarterback Jayden Daniels.

The cost to acquire Lattimore, 28, appears steep, but the Commanders had plenty of cap space and nine draft picks after dealing wide receiver Jahan Dotson to Philadelphia and defensive tackle John Ridgeway to New Orleans in August. They keep the third-round pick they received for Dotson and send over their other one, while also sending New Orleans the sixth-round pick it gave up in the Ridgeway deal.

Then there’s the salary: New Orleans restructured Lattimore’s deal last year, so Washington (7-2) takes on the remainder of his $1.21 million salary this season. Lattimore’s final two years of the deal include salaries of $16 million and $16.5 million, but they’re not guaranteed, so Washington could ostensibly sign him to a new, more cap-friendly deal.

Three months ago, such a trade seemed inconceivable in Washington. The Commanders had just started a massive rebuild, overhauling the front office, coaching staff and roster. They were a mystery team and seemed to enjoy being the unknown.

But nine games in, there’s no mystery about the Commanders’ rise, which is due in large part to the play of Daniels. The 23-year-old is on track to win offensive rookie of the year, if not more, and has helped to transform Washington from an afterthought (and in recent years, a blemish) to a contender with a prolific offense.

Among the glaring weaknesses, however, was the back end of the defense.

The Commanders drafted cornerback Emmanuel Forbes Jr. in the first round of the 2023 draft, believing his FBS record of six interceptions returned for touchdowns at Mississippi State would translate to more takeaways for Washington.

But Forbes had a rocky first season, with injuries and performance issues, and hasn’t fared much better in year two. A thumb injury cost him two games in September, and then he was a healthy scratch Week 6 against the Ravens, a clear indicator of his standing with the team. He did not play at all in the Commanders’ win over the New York Giants on Sunday.

To adjust for injuries and poor play in the secondary, the Commanders shifted rookie slot cornerback Mike Sainristil outside, opposite Benjamin St-Juste, one of the most targeted cornerbacks in the league, and have used Noah Igbinoghene in the slot in nickel packages (five defensive backs).

Lattimore gives the Commanders a clear starter, which should allow them to move Sainristil back inside.

Coming out of Ohio State, Lattimore was top the cornerback selected in the 2017 draft, taken 11th overall by the Saints. He earned the NFLs’ Defensive Rookie of the Year honors that season along with his first of four Pro Bowl selections (2017, 2019-21). His recent years, however, have been hampered by injuries — a lacerated kidney in 2022, an ankle sprain in 2023 and a hamstring injury this season. Of the Saints’ last 43 games, Lattimore has started and played in 34 of them.

Lattimore has been at the center of trade speculation for the better part of a year, since the Saints restructured his deal in December, so his exit isn’t a big surprise.

In Washington, he could be one of the centerpieces of a defense that is still finding its way.

The Commanders have improved significantly on that side of the ball since the start of the season to rank fifth in passing yards allowed (183.3 per game) but 21st in yards allowed per attempt (6.85). Washington has allowed the fifth-highest passer rating (103.9) to opposing quarterbacks and the third-highest rate of explosive passes (17.8 percent of attempts), according to TruMedia.

Lattimore’s arrival reflects Washington’s view that it’s ready to compete. At 7-2 and atop the NFC East, Washington is finally in contention to be a significant player not just this season but in the near future. General manager Adam Peters has stressed a desire to build the roster through the draft, to create continuity and keep the cap manageable.

The Commanders’ 2024 rookie class has produced four starters, plus two others who play a significant number of snaps each week.

To help develop the rookies and set a tone on and off the field, the Commanders signed a slew of proven veterans to shorter-term deals in the offseason — players such as linebacker Bobby Wagner, running back Austin Ekeler, tight end Zach Ertz and safety Jeremy Chinn. Doing so has given Washington an influx of leadership and talent while keeping the future flexible.

It also leaves Washington with plenty of decisions to make and holes to fill; 28 players will be unrestricted free agents in March, unless they re-sign earlier.

Lattimore is more of a splurge, indicating the team views him as a player who can help them win now and later.