Justin Verlander and Dallas Keuchel Have Been a Lethal Duo in Houston

The Houston Astros are inching closer to their first World Series appearance since 2005. The offense has been a big reason why, but it's been their starting pitching that's helped take things to another level.

Already in mostly uncharted waters when looking back on their franchise history, the Houston Astros are on the brink of further distinguishing themselves from the Houston teams that have come before them.

This is the fifth League Championship Series the Astros have reached since their establishment back in 1962. And with a 2-0 series lead over the New York Yankees heading into Monday night's Game 3, they're just two wins away from being the second team in club history to punch a ticket to the World Series.

After their dismantling of the Boston Red Sox in the American League Division Series, it was rather evident that an offense led by Jose Altuve, Carlos Correa, and George Springer (among others) would be tough to handle in October. But with just four runs scored over their last two games -- both of which still ended up being victories -- we've also seen how great they are in other facets of the game, like in the field and on the pitcher's mound.

And when it comes to the rotation, Dallas Keuchel and Justin Verlander are leading the way as a formidable one-two punch.

Offense Is Great, But Something Was Missing

Baseball teams need to score runs to win games. Makes sense, right? But as we saw with the Colorado Rockies in the National League Wild Card game and Washington Nationals in the NLDS, scoring a bunch of runs doesn't matter when you also allow a bunch.

Armed with the best regular-season offense we've seen this century -- according to wRC+ -- Houston needed a boost during the dog days of August after mostly standing pat at the non-waiver trade deadline. That came in the form of a last-minute deal to acquire Verlander from the Detroit Tigers, and it paid dividends with regard to getting Houston back on track.

After the July 31st deadline came and went without a big splash, the Astros proceeded to post an 11-16 record during the month of August. Once the calendar flipped to September, they finished the regular season with a 21-8 clip the rest of the way, helping them eclipse the 100-win mark for the second time in franchise history.

Was it directly related to the acquisition of Verlander? Maybe, maybe not, but we can't argue with the on-field results, which included a 5-0 record from their new ace to go along with a 1.06 ERA supported by a 2.59 SIERA. And after a rough two-month stretch between July and August that included time on the disabled list, Keuchel returned to his early-season form that made him appear to be a Cy Young candidate.

Both Are Dominant in Different Ways

When it comes to forming a starting rotation -- whether it's for the regular season or the playoffs -- virtually any big league manager will likely be content with getting the best hurlers they can get their hands on. In a perfect world, though, it's even better when the styles of said hurlers differ, seemingly keeping hitters off balance to a degree.

That's exactly what manager A.J. Hinch has with Verlander and Keuchel headlining his postseason staff.

Verlander is a classic, hard-throwing righty who can consistently go deep into games. After recording an average fastball velocity under 95 miles per hour (MPH) in each season since 2011, the mustard returned in full force this year with a 95.2 MPH average that paired nicely with his slider. And despite early-season struggles in Detroit, the veteran failed to complete at least five innings just three times in his 33 starts. He's also pitched into at least the sixth inning in each of his last 18 starts.

On the other hand, Keuchel is a southpaw who averaged 88.7 MPH on his fastball in 2017. He was also heavy on the slider but depended quite a bit on his changeup and cutter, too. We can see how different their approaches when looking at some results from the regular season.

The below table shows how these two compare against one another with regard to ground-ball rate (GB%), fly-ball rate (FB%), strikeout rate (K%), swinging-strike rate (SwStr%), and SIERA.

Player IP GB% FB% K% SwStr% SIERA
Justin Verlander 206.0 33.5% 42.7% 25.8% 10.7% 4.05
Dallas Keuchel 145.2 66.8% 17.7% 21.4% 10.9% 3.61

Outside of the batted-ball numbers displayed, they actually don't look that different, right? But if we zero in solely on Verlander's time with the Astros, the contrast becomes more stark.

Through his 34 regular-season innings with Houston, the right-hander produced a 32.4% ground-ball rate and 47.9% fly-ball rate to go along with a 35.8% strikeout rate, 14.2% swinging-strike rate and that 2.59 SIERA we mentioned before. This is clearly a very small sample size, but it also helps further show us how Verlander and Keuchel use different approaches to reach the same successful result.

It's on Display in October

With a squad that's gone 5-1 in their first six postseason games, there's plenty of success to go around for the roster. But when it comes to the pitching staff, it has to start with Verlander and Keuchel, since they're the ones setting the tone.

Keuchel has actually racked up strikeouts more often than Verlander so far this postseason (34.7% strikeout rate to 24.2%), but they've stayed true to their respective approaches en route to combining for all five of Houston's victories to this point in October (in four starts and one relief appearance). Verlander has remained reliant on fly balls (53.3% fly-ball rate and 28.9% ground-ball rate), while Keuchel has induced ground balls at a 57.1% rate and has limited opposing hitters to fly balls just 17.9% of the time.

Let's not forget that this is all being done without Lance McCullers being a part of the postseason rotation -- uneven performance and injury in the second half derailed what could've been a special season. It's also relegated him to bullpen duty during the playoffs.

With Brad Peacock and Charlie Morton rounding out the starting staff during their quest for a World Series title, they're in a great situation. Not only do they have the rotation depth to be consistently productive, but they also have a solid one-two punch leading the way with varying styles that can give opposing hitters drastically different looks.

Things aren't just looking good with regard to reaching the franchise's second Fall Classic this season -- our models give them an 82.40% chance of advancing prior to Game 3 -- they appear to be in a great position to do the same thing next year, too.