The Washington Nationals are nearing the end of one of the most radical and risky offseason roster renovations you will ever see. By taking chances at almost every turn, the Nats have set themselves up to be spectacularly right or shockingly wrong. They seem determined to prove you can lose Bryce Harper — and several other key players — yet end up with a better team. Or discover that 82-80 is their new normal.

In every move they have made, they have gambled more and aimed higher than I would have. In coming days, when they probably add a second baseman and at least one more pitcher, they may surprise us again — in both potential upside and daring acceptance of a scary downside.

If the Nats sign second baseman Jed Lowrie, coming off an all-star season that included 99 RBI for the 97-win Oakland A’s, or go for a top bullpen arm such as David Robertson or Adam Ottavino, they will surprise me again. But it would fit the pattern. Or maybe they will go after left-hander Wade Miley, the best hurler left in a picked-over starting-pitching market.

After the moves the Nats have made, my disbelief is officially suspended. At $140 million for six years, I probably would have backed away from lefty Patrick Corbin. But they jumped in when others stopped at $100 million. It’s exciting that he’s in D.C. He will be in the same rotation with Max Scherzer for three years and with Stephen Strasburg for as many as five more years. That could look brilliant.

But Corbin, who turns 30 in July, has had major elbow surgery. He has never won more than 14 games in a season and owns a 56-54 career record. He does throw an amazing slider, at varying speeds, on half of his pitches. Is that sustainable?

Ever since I watched Steve Stone decide to throw 60 percent curveballs in 1980 — and win 25 games and the Cy Young Award — then blow out his arm, career over within a year, I have always shuddered at huge increases in breaking ball usage.

The Nats could have been sensible and gone after Charlie Morton (35) or J.A. Happ (36), both coming off very good seasons, who signed two-year deals for $30 million and $34 million, respectively. But General Manager Mike Rizzo and the Lerners went for the ring — brass or World Series.

The Nats traded right-handed starter Tanner Roark and replaced him with free agent Anibal Sanchez, 34, who made 24 starts in 2018 with a 2.83 ERA after being dismal the previous three years. I would have kept the workhorse Roark, not the less-durable Sanchez, who is now on the books for $19 million over two years. If it works, it could be a rotation full of sizzle with 2020 covered, too. But fizzle is possible, too.

One reason for Sanchez’s rebirth last season in Atlanta was his work with catcher Kurt Suzuki. Analytics helped them go with more cutters and change-ups, fewer fastballs and sliders. Can it be that simple? We’ll find out — because the Nationals signed Suzuki earlier this offseason, allowing the pair to continue their experiment. In fact, having Suzuki in house almost certainly encouraged Sanchez to sign with the Nats.

Once they signed the 35-year-old Suzuki, who suddenly appears to have learned how to hit — and hit with some power — in his 11th and 12th pro seasons, I thought the Nats would probably be satisfied with the upgrade, back him up with kids and cross their fingers. Instead, they traded prospect Jefry Rodriguez for Cleveland catcher Yan Gomes.

In Corbin and Gomes, the Nats have added a battery of 2018 all-stars.

Perhaps the Nats’ biggest under-the-radar gamble was the contract they gave reliever Trevor Rosenthal, who didn’t pitch last season while he recovered from elbow surgery. The man with the 100-mph fastball, plus a nasty change-up and slider when he’s healthy, is only guaranteed $7 million. But if he pitches in 50 games — a total the Nats hope and assume he will reach as their primary setup man for Sean Doolittle — he will vest into a two-year deal worth at least $26 million, plus performance bonuses.

This is the same deal structure that Greg Holland, after the same surgery, signed before 2017 with Colorado. Same agent: Scott Boras. How did that work out? Holland led the National League in saves (41) in 2017. But he struggled badly last season before bouncing to the Nats late in the year and ending with a 4.66 ERA.

Last week, the Nats did an admirable job of filling another spot — a slugging lefty-hitting Matt Adams-type to back up Ryan Zimmerman at first base. The Nats found the perfect man — Matt Adams.

What’s next?

The modest blueprint, one that the Nats certainly could execute since they are $14 million under the luxury tax threshold, would be to sign free agent second baseman Josh Harrison, a two-time all-star in Pittsburgh coming off a disappointing 2018, as well as a lefty-specialist reliever (Justin Wilson or Tony Sipp), then bring back twice-through-the-order starter Jeremy Hellickson.

After such an adventurous offseason, I doubt the Nats finish by playing it safe. With Harper as good as gone, they need to add power, preferably left-handed or switch-hitting. Lowrie would be ideal, if they can afford him.

Lowrie will be 35 in April. Perhaps his past two seasons — 37 homers and 168 RBI combined — could represent a career peak for a smart grinder from Stanford. But if you want to gamble — the Nats’ pattern — Lowrie’s wins above replacement for 2017-18 (FanGraphs) was 8.5. Harper’s was 8.3. Harper owns the future. But if you can get him for two years, Lowrie sure might help before making room for prospect Carter Kieboom.

In the glutted second base market, switch-hitting Marwin Gonzalez would be a nice catch with 15- to 20-homer pop. But the tempting lottery ticket is Brian Dozier, one of the lowest-paid stars of recent years. FanGraphs says his past six years, with an average of 28 homers, plus speed and a Gold Glove in 2017, were worth more than $175 million in free agent dollars. Dozier’s career earnings: $21 million.

His stock is down after a season in which he hit just .215 with 21 homers. Like everyone in this second base basket, he has a positive clubhouse reputation. But Dozier has a skill the others lack: power. He hit 42 homers in 2016, 34 the following season. He would fit right into the Nats’ roll-the-dice offseason.

The Nats are approaching the finish line of a crucial culture-shifting offseason that they have anticipated for the past two years — gone are Daniel Murphy, Gio Gonzalez, Matt Wieters and Ryan Madson. Harper is a good bet to be playing elsewhere, too.

Whether through player development (Juan Soto and Victor Robles) or trades (Adam Eaton) or, this winter, with both free agent signings and trades, the Nats have tried to prove that the kind of mass migration that destroys some franchises could be an opportunity for them.

They’re getting close. Just a couple of more important moves to make. What will they be? Given everything the Nationals have pulled off in getting to this moment, bet on the bang, not the whimper.

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