The Washington Nationals are nearing the conclusion of one of the most important weeks of their season, having played six games against the Atlanta Braves and Philadelphia Phillies. The Nationals, 4-1 in those games, could have easily ran the table thus far. Yet on Saturday their bullpen turned a late four-run lead into a four-run defeat. In a testament to how this week has the Nationals approaching things with a renewed sense of urgency, on Sunday the club released one of the pitchers responsible for the meltdown: right-hander Trevor Rosenthal.

Rosenthal, signed to a one-year deal worth $8 million over the winter, is the author one of baseball’s worst seasons.

That’s not an exaggeration or an attempt at being meanspirited so much as it is a description of his season. Rosenthal had thrown 6 1/3 innings in 12 appearances, walking 15 of the 43 batters faced and hitting another three while permitting eight hits and 16 runs and uncorking five wild pitches. He began his season by failing to record an out in any of his first four appearances.

To Rosenthal’s credit, he’d pitched better upon returning from the injured list in early June. Prior to Saturday, he had held the opposition to one run on one hit in 3 1/3 innings. He’d even thrown 63 percent strikes. Alas, he had still recorded more walks (three) than strikeouts.

Because Rosenthal has a track record of being a legit big-league pitcher, and because he averaged 98 mph on his fastball, he’s likely to find another gig in the coming weeks. There’s no telling if he’ll ever be able to find his release point consistently enough to rediscover success. Given the extremity of his struggles, it’s fair to wonder if the cause is more mental than physical.

In a corresponding move, the Nationals promoted Austin Voth.