Ex-Padres pitching piece from 2021 deadline trade outrighted by Nationals

The 2021 deadline seems ages ago, and it wasn’t just hectic for the San Diego Padres, it was a full-on identity play. A.J. Preller shoved his chips in for bullpen help and treated live arms like currency. Mason Thompson was one of those chips, a big righty with a bowling-ball sinker and just enough prospect sheen to spark “what if” daydreams. Four years later, the verdict isn’t romantic: Washington outrighted him off the 40-man, and he chose free agency. The helium completely leaked out.

Call it a late-October footnote if you want, but it closes the loop on a classic Padres deadline bet. On July 29, 2021, San Diego paid in upside, Thompson and Jordy Barley, to rent certainty in Daniel Hudson. Everyone understood the math. Contenders buy leverage innings; rebuilders buy time. The twist is how long it took for Thompson’s side of the equation to land with a thud.

Padres’ 2021 trade piece Mason Thompson gets outrighted by Nationals

The raw ingredients were always there. A third-round pick in 2016, Thompson debuted with San Diego, essentially making four cameo appearances (3.00 ERA in three innings) before heading east. In D.C., he looked the part in spurts: heavy ball, deadened launch, grounders for days. But the full picture never sharpened. Across 114 MLB innings, the 50.6 percent ground-ball rate plays; the 5.21 ERA, 17.8 percent K rate, and 11.1 percent walk rate absolutely do not. That’s not leverage; that’s limbo.

Then the elbow hijacked the story. Tommy John wiped out his 2024, erasing whatever momentum he had. By 2025, the option clock was out of patience, too. He burned his final option this year, which meant 2026 would come with no safety net to fix command on the fly. For a reliever trying to live at the margins, that’s checkmate.

So the Nationals did what teams do in October triage: they cleaned the edges, and Thompson was one of the cuts. With three-plus years of service, he didn’t have to take the minor-league assignment, and he didn’t. He’ll be 28 in February, young enough for a pitching lab to squint and see chase-rate gains in a sinker/slider mix, old enough that the next contract probably reads “non-roster invite.”

To be fair, Hudson wasn’t exactly a home run either, 1–2 with a 5.21 ERA over 23 appearances. For Padres fans, this is less heartbreak than history lesson. Preller spent a ground-ball arm to buy stability in 2021, and Thompson never solved the strike-throwing riddle in Washington. Maybe a trimmed walk rate and a small whiff bump unlock a middle-innings role somewhere else. Maybe not. Deadline fine print rarely flatters anyone: the headline hits in July; the epilogue shows up years later, tucked in the transaction wire.