Matt Wieters will be back behind the plate for the Nationals in 2018. (Brad Mills/USA Today Sports)

As had long been expected, catcher Matt Wieters exercised the 2018 player option in his contract and will return to the Nationals next season, according to a person familiar with the situation. Wieters will earn $10.5 million in 2018, completing a two-year deal worth $21 million total.

Wieters could have chosen free agency but likely would have earned far less than what will now be his 2018 salary after he struggled through this past season. The 31-year-old hit .225 with a .632 on-base-plus-slugging percentage, the lowest OPS of all catchers with at least 400 at-bats. He experienced a memorably poor defensive inning in Game 5 of the National League Division Series, one that led him to taking the blame for Max Scherzer’s grisly outing in that game.

He had the third-lowest defensive Wins Above Replacement of qualified catchers this season, threw out 25 percent of runners trying to steal — 21st-best in baseball — and allowed 76 steals, fifth-most in baseball. But, generally, Nationals pitchers praised Wieters’s game-planning and pitch-calling instincts.

That Wieters will exercise his option clarifies the Nationals’ catching situation somewhat, though the bigger question has to do with their other catcher for 2018. Jose Lobaton is a free agent. Pedro Severino is big league-ready. Will the Nationals let Lobaton go and promote Severino to be the major league backup? Will they sign a veteran catcher to serve as the backup or perhaps even split time with Wieters? And with $10.5 million committed to one catcher, how much would the Nationals be willing to spend on another?

For now, Wieters is the presumptive starter, and he’s probably due for some sort of progression to the mean. His average dipped nearly 30 points below his career mark, though it has dropped by 20 points or more each season since he hit .308 in 2014. His strikeout rate was the third-highest of his career, and his hard contact percentage was the second-lowest. But his batting average on balls in play was well below league average, and he tinkered with his mechanics for much of the season, struggling from both sides of the plate.

Wieters played 123 games after playing 124 in his last season with Baltimore, and he is likely best used for 120 or fewer instead of the 140-plus he used to catch annually. The Nationals used Lobaton sparingly in 2017 as he struggled offensively. Next season, they will likely need someone to play 40 or more games, even with Wieters returning.

Severino could be a semi-regular fill-in. Lobaton will not cost much, and Nationals pitchers praise his framing and demeanor. The range of catchers available in free agency this winter includes everyday types like Jonathan Lucroy and well-regarded veteran part-timers like Alex Avila, Nick Hundley and Chris Iannetta. Exactly what Wieters might have gotten in that market remains unclear. But he will not hit that market, and the Nationals will pay him $10.5 million, the eighth-highest salary on their roster.

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