Tanner Rainey needs to play a key role for the Washington Nationals in the World Series

As the Washington Nationals prepare for their first ever World Series game today — yes, this is still real and is happening — a lot of the focus on the team is around the bullpen. Again.

So far this postseason, the Nats have managed to hide their glaring weakness pretty well.

In the five-game series against the Los Angeles Dodgers, the Nationals were able to utilize Patrick Corbin and Max Scherzer out of the bullpen to try and protect narrow leads.

Then, in the NLCS against the St. Louis Cardinals, the Nats starting pitching took over again, but this time in their day jobs. Well, aside from a one-batter appearance from Corbin.

The “Big Four” accounted for 27 of the 36 innings pitched by the Nationals in the sweep, while Sean Doolittle and Daniel Hudson got six between them, closing out the games.

That definitely won’t be the case in the World Series. The Houston Astros are a completely different beast to the Cardinals team the Nats saw, boasting one of the best lineups in baseball.

Simply put, they’re going to need other pitchers to step up in the bullpen to have a chance.

Aside from the four starters and the two relief aces, only two other Nats pitchers have entered the game holding a lead this postseason. Tanner Rainey and Fernando Rodney.

Of the two, it seems as though Rainey, the fireball-throwing right-hander, is the next man up in the bullpen. Manager Dave Martinez trusted him to keep Game 5 close out in LA and also with a three-run lead when Corbin had an abbreviated outing in Game 4 of the NLCS.

“I told Tanner Rainey all the time,” Martinez said at the team’s workout day, “it doesn’t matter what inning you’re pitching in, you just need to get outs, and that’s the way I want you to look at it, because it’s the seventh or the eighth, or even the fifth of sixth, just get outs.”

GM Mike Rizzo has also seen the potential that Rainey has put on display this postseason.

“You look at his numbers, and when he’s in the strike zone, people have a tough time squaring him up,” Rizzo told 106.7 The Fan’s Sports Junkies.

“The batting average against is below .200, and when he’s throwing strikes he’s tough to hit, so he’s really come into his own at the latter part of the season, and as he has emerged.”

However, don’t sleep on the “when he’s throwing strikes” part of Rizzo’s analysis. As it has been his whole career, command is a big knock on Rainey and currently keeps him from establishing himself as one of the best relievers in baseball, which isn’t an exaggeration.

Rainey has a heater that can hit triple-digits frequently and, as Mike Petriello of MLB.com pointed out in his recent article about the reliever, his slider is downright disgusting. It’s a similar arsenal to the one that Aroldis Chapman possesses from the left-side.

But when the command fails him, the results can be disastrous. Nats fans who remember Henry Rodríguez know how badly the high-velocity, no-command combination can go.

For Rainey, thankfully, it seems to be a consistency issue rather than an issue of never having his command. He walked multiple batters in 9 of his 52 regular season appearances, which no doubt isn’t great, but when he allows one or fewer walks, he holds a 2.16‬ ERA.

His manager did get a little carried away with his stuff straight after his call-up, using him as a setup man with the rest of the bullpen continuing to implode. Eventually, he settled into a much more comfortable, while still fairly high-leverage role.

“I think Davey has really put him into a position to succeed,” Rizzo also told The Junkies.

“[Rainey] really has great success against right-handed hitters, and is still learning how to get those really good left-handed hitters out.

“So I think that you see Davey really can kind of pinpoint where — we have a block of the lineup that we like to use Tanner in, it’s mostly against the right-handed strong part of the lineup, and you saw the occasions that he’s pitched recently, he’s getting two or three or four right-handed hitters in a row, and he’s done a whale of a job getting those guys out.”

Though not used strictly as the right-handed version of a LOOGY, as he does still face a lot of lefties, Martinez has made use of Rainey’s ability to nail down right-handed hitters.

During the regular season, right-handers put up a measly .139/.298/.228 slash line against Rainey, compared to a much better .261/.420/.522 line for left-handed hitters.

While Martinez has done a good job of carefully managing where to use Rainey so far this postseason, he’s going to need to rely on him more throughout this series if the Nationals are to have any success against the Astros.

There are much much easier matchups for Rainey to thrive in — where are the Kansas City Royals when you need them? — however, with some of the analytics at play, the right-hander may have a slight upper-hand against the formidable Astros lineup.

According to Baseball Savant, the Astros have a .208 wOBA against four-seam fastballs of at least 98mph, the seventh-lowest in the majors during the regular season.

Attacking them with Rainey’s super-charged velocity could pay dividends if those struggles from the regular season carry over for Houston, especially with a right-handed-heavy lineup.

A counterpoint to this is that the Astros then sport the highest wOBA in the majors against sliders with a velocity of 87mph or higher, with a .376 figure, also per Baseball Savant.

Their blueprint could easily come from the same strategy that José Altuve used against Chapman in Game 6 of the ALCS to send the Astros back to the Fall Classic.

The left-hander was struggling to command his fastball during the inning, using his slider to try to recenter his command. Because of this, Altuve sat on Chapman’s slider the whole at-bat and ended up smacking one off the left field wall for a series-winning home run.

Maybe that changes with a righty compared to a lefty, but the Astros hitters are going to be some of the toughest that Rainey has faced, regardless of which box they stand in.

On the national stage, Rainey probably still qualifies as a secret weapon who not many outside of those who follow the Nationals know. He has a chance to announce his presence with authority if he can be an integral part of the bullpen during the World Series.