HOUSTON – Their personalities are drastically different; they grew up on different sides of the country, born seven years apart; but at times, they act so eerily similar.

The one with the receding hairline and slowly forming bald spot, walks into the Houston Astros clubhouse the day he pitches, wearing headphones, a scowl on his face, and talks to no one. The other chats to everyone but the peanut vendors on the days he starts, talking to teammates on the bench, asking everything but what they had for lunch. One is an avid golfer who plays Pebble Beach; the other lives in Southern California but would much rather be on a surfboard than a golf course.

The pitcher who has established a Hall of Fame career competes against people, knowing his legacy is being compared against his peers and those who came before him. The other is slowly starting his Hall of Fame resume and competes against the game, as if he’s trying to perfect the art of pitching, while wanting his teammates to rely on his greatness.

Together, in the year of the home run and juiced baseballs, while pitching for a franchise that values analytics more than any other team in baseball, Justin Verlander and Gerrit Cole put on the greatest old-school pitching show in baseball.

“What they are doing is amazing, probably the best duo in baseball history," Astros All-Star second baseman Jose Altuve said. “I don’t know which would be harder, facing those guys or trying to pick which one wins the Cy Young. Thank God, I don’t have to make that decision."

These teammates, whose lockers are side-by-side, are the finest two pitchers in the game this year, putting up numbers that are almost impossible to distinguish from one another with the naked eye.

When the season ends, it’s almost guaranteed that Verlander and Cole will become the first teammates in nearly two decades to finish 1-2 in the Cy Young balloting. The last to accomplish the feat were Randy Johnson and Curt Schilling in back-to-back years in 2001-2002 with the Arizona Diamondbacks.

“That was a two-headed monster, just like what we’ve got going here," Astros Hall of Fame second baseman Craig Biggio said. “To have one horse is something, but to have two of them, that is pretty special."

You want to see a terrifying sight?

Verlander is a league-leading 18-5 with a 2.52 ERA and 265 strikeouts and 35 walks in 200 innings, yielding a .166 batting average and 0.77 WHIP (walks plus hits per nine innings). If he maintains this pace, he will have the lowest opponent’s batting average and second-lowest WHIP by any starter in baseball history.

Cole is 16-5 with a 2.73 ERA and major-league leading 281 strikeouts and 43 walks in 184 1/3 innings, yielding a .189 batting average and 0.92 WHIP. He is just the second to strike out at least 14 in three consecutive starts. His 13.72 strikeouts per nine innings would be the highest in baseball history.

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Verlander, who has a 1.21 ERA in his past five starts, has thrown a no-hitter this season, the third of his career, becoming only the sixth pitcher in history to accomplish the feat. Cole followed up by yielding one hit and striking out 15 in eight innings, becoming only the fourth pitcher in history to have six starts in a season with 10 or more strikeouts and no walks.

The duo became the first teammates in Major League history to strike out 14 or more batters in consecutive games.

Go ahead, you make the Cy Young call.

“They have different personalities, they have different approaches, even their game plans are different," Astros manager A.J. Hinch said. “But when you peel it back, there’s a common thirst for greatness and dominance. There’s an 'it' factor that JV has always had, and Gerrit has developed into his own the last couple of seasons. They feed off each other and compete against each other in a healthy way like brothers do.

“In a year where the ball is flying out of the ballpark, the numbers are inflated, and we’re seeing unprecedented power and offensive production, they are putting up historic seasons on the mound.

“I can’t imagine having a better tandem no matter how long I get to manage. I don’t know how you can top this."

Each has four scheduled starts, and if nothing dramatically changes, Verlander, 36, should walk away as the oldest Cy Young award winner since 42-year-old Roger Clemens in 2004. Cole should emerge as the richest pitcher in baseball history when he hits free agency this winter.

“That’s fair enough," Verlander, said, laughing, “I’m going to tell him you said that. But seriously, it would mean a lot to me. Not just because of my age, but having gone through being at the top of my game, to going down and being hurt and having people count me out, to getting back to where I am now. Yeah, that would be special, particularly coming close so many times."

Verlander and Cole, sitting down in separate interviews lasting nearly 90 minutes with USA TODAY Sports this week, talked about their seasons.

Cole, who will become a free agent this winter and the most coveted pitcher on the market, embraces the importance of his role as the standard-bearer in the market. Future free agents will feed off his deal. He could wind up shattering David Price’s free agent record contract of $217 million over six years. All he has to do is point to Verlander, who’s dealing at 36, to let potential suitors know that long-term contracts can pay off. Look at how the Washington Nationals’ $210 million investment in Max Scherzer has paid off.

“I really haven’t put too much thought into it yet," Cole said, “but what guys like Justin and Zack (Greinke) are doing, they’re living proof that it’s humanly possible to maintain most of your stuff at 36. What Justin is doing, it sets an example for all of us. Really, it’s inspiring."

There will be plenty of time for victory speeches, thank-you messages and hugs before Verlander and Cole are expected to part ways after the season. Verlander signed a two-year, $66 million extension this spring to stick around town. It’s far-fetched to believe the Astros will want to pay nearly $100 million annually to keep Verlander, Greinke and Cole together past this season.

Maybe they can officially say their goodbyes at the Baseball Writers Association of America’s award dinner in New York, where one will accept the 2019 Cy Young and the other may be there knowing he was responsible for the greatest 1-2 finish among teammates since Johnson and Schilling.

“We don’t bring up the Cy Young stuff," Cole said. “We know it’s there, but we don’t need to talk about it. I came across a quote recently from (author) Peggy Noonan, and she said, 'If you have a competitor running in the same race and when you’re done, sometimes you wish you enjoyed just running the race.' I thought that was really applicable.

“It’s important to me just enjoying being next to him and to appreciate what we’re doing. I don’t take it for granted."

Verlander said, “I think all of the best rotations ever always had guys that push each other. I think that’s the best atmosphere for success. We have this competitive balance/friendship thing, and we don’t shy away from it. We go back and forth all of the time. But as I told him, we keep this rolling into October, and we’re onto something special. We expect to succeed in October. We’re not going to shy away from the moment.

“And winning a World Series together with him, there’d be nothing like it."

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