Gio Gonzalez could be a difference-maker against the Dodgers. (Toni L. Sandys/The Washington Post)

Let’s establish two things: For fans of the Washington Nationals, it’s not too early to talk about the playoffs. And since we’re talking about the playoffs, get comfortable with the idea the key to advancing past the first round might just be one Gio Gonzalez.

“I’ve been fortunate to pitch in a couple playoff games, and each one has been just as hard as the other,” Gonzalez said this week. “It’s never an easy task.”

To which a giant subset of Nationals fans would respond: Watching Gio Gonzalez pitch is never an easy task, either.

Put aside the optics, though, and let’s talk about the opportunity – and the opposition.

The Nationals enter the weekend with 16 games to play and a 10-game lead over the Mets. They are going to win the National League East. They also entered Thursday night trailing the Cubs by 6-1/2 games for the NL’s best record. They’re not going to catch the Cubs for the top seed. Therefore, they are almost certain to face the Dodgers, who lead the NL West by five games over reeling San Francisco.

What does this have to do with Gonzalez? Well, Gonzalez pitches with his left hand. And the Dodgers are dreadful – and by “dreadful,” we mean hard-to-watch, worst-team-in-baseball awful – against men who pitch with their left hand.

Told this, Gonzalez said, appropriately, “I don’t know, man. Look at them.”

The parts, of course, include dangerous left-handed hitters Corey Seager, Adrian Gonzalez and Chase Utley. Each has struggled against lefties this year. None is likely to sit in the playoffs.

Look at the Dodgers as a whole, though. Pick a category against left-handers, and consider the Dodgers’ position. The average major league team hits .256 against lefties. The Dodgers are hitting .213 against them. That’s not just last in baseball, it’s lastby 19 points. Against lefties, they own an on-base percentage of .293; that’s last in baseball. Against lefties, they slug .334; that’s last in baseball. (The Nats, in contrast, slug .457 against lefties.)

Put another way: This year, 152 players have enough plate appearances to qualify for the batting title. Three (3) have a worse on-base-plus-slugging percentage than the Dodgers entire roster against left-handed pitching — .627, which is, say it together now, last in baseball.

One more stat: As you would expect, Gonzalez is better against left-handed hitters (.212 average and .579 OPS allowed) than he is against right-handed hitters (.262 average, .751 OPS). Baseball is supposed to work that way, and Gonzalez does his part.

Add it all together, and it becomes apparent why one National League executive, someone not involved in what would be a Dodgers-Nationals series, said last week, “I think Gio is the most important aspect of that series.”

Not Max Scherzer, who is now the favorite to win the Cy Young award. Not Tanner Roark, who has been nearly as good. Not Bryce Harper, who won the MVP award last year. Not Daniel Murphy, who is contending for it this year.

Gio Gonzalez, the key to beat the Dodgers. Is he ready for it?

“I don’t think there’s one pitcher that goes in there to a playoff game saying, ‘Well this is a normal thing and I’ve just got to go out there and do what I’ve got to do,’” Gonzalez said. “The games get a little bit longer. Hitters are a little bit more patient. Every out is extremely tough. You have to focus a little harder and just execute your pitches.”

This is where Nats fans would plead with Gonzalez to do exactly that: Focus a little harder and just execute your &*%#$@! pitches.

But in accepting that Gonzalez is a crucial part of the nearly inevitable Dodgers-Nationals division series, Washington fans must first accept that Gonzalez is, in fact, a good pitcher.

Watching him live, it’s impossible to put aside his penchant for responding to runs the Nationals’ lineup grants him by immediately granting runs back to the opposition. Watching him live, it’s impossible to ignore how he slows down when trouble arises, how he throws too many pitches (17.3 per inning, second most in the NL), how you can leave the television to get a drink and a sandwich and basically be assured to get back to the couch before the inning is over. Nats officials would prefer he pitch as he did Sunday, his most recent and best start of the year, when he worked quickly against Philadelphia and, lo and behold, tossed seven innings of one-run ball.

But really, if you never watched Gonzalez pitch, you wouldn’t have much of a problem with Gonzalez as a pitcher. Since joining the Nationals in 2012, Gonzalez has now thrown 893-2/3 innings. Here is the complete list of pitchers who have pitched more innings and have an ERA lower than Gonzalez’s 3.54 during that time: David Price, Max Scherzer, Madison Bumgarner, Cole Hamels, Jon Lester, Clayton Kershaw, Felix Hernandez, Justin Verlander, Chris Sale, Zack Greinke, Jose Quintana, Johnny Cueto and Jordan Zimmermann.

No, it’s not a particularly short list. But it’s certainly chock full of the best pitchers in the sport. There are indicators of recent success, too, what with Gonzalez’s second-half ERA of 3.54, a number befitting a pitcher who could be handed the ball in the second or third game of a playoff series.

This is not to make Gonzalez out to be one of the best pitchers in the sport. It is, though, to say in a matchup of Dodgers and Nationals, Gonzalez could swing the series. Washington went 1-5 against Los Angeles this season. The one win: July 20, when Gonzalez threw six innings of one-run ball.

“Baseball’s a tricky sport,” Gonzalez said.

That it is. Tricky enough that a soon-to-be-31-year-old left-hander with a history of frustrating his own fan base could be the most important piece in the quest to play deep into October.