|From the Atheltic|
Hudson is a free agent after the year, and is having a bounce back year. He has been in a set-up role for Ken Giles, and has his lowest single season ERA since 2010, when he was a starter. He will improve a weak Nationals' pen.
Hudson, 32, has a 3.00 ERA with 48 strikeouts and two saves in 48 innings for the Blue Jays this year. In his MLB career for the Blue Jays, Los Angeles Dodgers, Pittsburgh Pirates, Arizona Diamondbacks and Chicago White Sox, Hudson has a 3.92 ERA with 593 strikeouts and 11 saves in 667.2 innings.
The Jays are rebuilding, and a pending free agent in Hudson doesn't help them. They get Johnston in return, the 27th best prospect in the Washington, per MLB Pipeline.
Johnston, 23, has a 4.03 ERA with 100 strikeouts in 105 innings for High-A Potomac. In his minor league career, he has a 3.93 ERA with 229 strikeouts in 254.1 innings.