July 13, 2017 12:12 GMT by espn.com

Who -- or what -- can stop the Washington Nationals?

Who -- or what -- can stop the Washington Nationals?

The first half was a breeze, but NL East-leading D.C. is no lock for second-half dominance. Here are some potential roadblocks en route to October.

It was a breeze of a first half for the Washington Nationals. As we emerge from the All-Star break, the Nats have a 9½-game lead in the NL East. Their .591 winning percentage is the fourth-best in baseball. Of the 102 days in the season, they've had at least a share of first place for 99, more than any team in the majors.

That's not to say there's nothing to worry about in the second half. Here's a list of five things that could derail the Nats in their attempt to make the playoffs in back-to-back seasons for the first time since moving to D.C.:

1. THE BULLPEN: Just how bad have Washington's relievers been this season? Their 5.20 ERA is the worst in the baseball. Their closer situation is such a mess that they've had six different hurlers record at least one save. Their 4.1-percent home run rate is the highest in the National League, and they're the only unit that's allowing opponents an OPS of more than .800 (.819, to be exact). In theory, dealing for help prior to the trade deadline should make the Nats -- who've made three early exits in three postseason appearances -- a tougher October out. But what if the bullpen continues to fail so profoundly that Washington whiffs on the postseason? Unlikely? Yes. Impossible? Not entirely.

2. INJURIES: The good news? Ace Max Scherzer and the rest of the rotation have stayed healthy, a big reason the Nats are where they are. The bad news? The injuries are piling up on the other side of the ball.

The season-ending injury to leadoff man Adam Eaton seemed like a doozy when it happened in late April, but Michael A. Taylor has been a super sub since. Thing is, now Taylor's dinged up with a strained oblique, and obliques have been known to linger. Speaking of lingering, left fielder Jayson Werth's "bruised" foot has kept him out for more than a month. The biggest boo-boo of all is the broken wrist Trea Turner suffered. In 68 games with Turner in the lineup, the Nats average 5.7 runs per game. In 18 games without the speedy shortstop, that number dips to 4.9. In the seven games since he fractured his wrist, they're scoring just 4.3 per contest. Where I come from, that's what's known "trending in the wrong direction."

3. BEING TOO GOOD: The Nationals sent five players to the All-Star Game, tied for the most of any team (not including replacement players). Bryce Harper, Ryan Zimmerman, Daniel Murphy, Scherzer and Stephen Strasburg all had standout first halves and all deserved to be there. As a result, their All-Star "break" isn't a break at all.

"The All-Star Game is draining," skipper Dusty Baker said last week. "There's a lot of hoopla, you sign 10,000 balls. You do this banquet, that banquet. So I may have to rest a guy or two after the All-Star break." Not exactly the kind of position a manager wants to be in to start the second half, especially when it comes to his studliest players.

4. DUSTY'S CONTRACT SITUATION: The Nationals have been so good under Baker it's easy to forget he wasn't their first choice (Bud Black was). That might have something to do with the fact, despite a .588 winning percentage since signing a two-year deal prior to the 2016 season, Baker has yet to receive a contract extension. Or it might have something to do with the fact that last year, under Baker, Washington lost in the first round of the playoffs. Again. Regardless of the reason, the bottom line is that it's July and Baker still doesn’t have an extension. Although it hasn't reached major-distraction status -- not yet, anyway -- the situation has bubbled up at times. If it reaches a full boil at some point over the next couple months, you have to wonder how it might affect the Nats on the field.

5. THE ATLANTA BRAVES: No, really. The Atlanta Braves. If Jim Johnson hadn't blown a three-run lead in the ninth inning on the Friday before the break, the second-place Braves would be "just" 8½ games behind Washington. Point is, the Braves are sneaky good. OK, maybe sneaky good is a bit much. But at a minimum, they're sneaky better than you might think. Ender Inciarte is a legit top-of-the-order nuisance. Matt Adams, whom Atlanta acquired to play first base after Freddie Freeman went down in mid-May, has raked. Now that Freeman is back (and playing third base for the first time in his career), an offense that helped the Braves go 24-20 in his absence should be that much more dangerous.

Swapping out 44-year-old Bartolo Colon and his 8-plus ERA for 24-year-old former first-rounder Sean Newcomb (3.58 in five starts) improves the rotation, which has been led lately by red-hot R.A. Dickey. Is it enough for the Braves to dethrone the Nats as champions of the NL Least? Probably not, but there's plenty of baseball left to play (including six games between Washington and Atlanta), and hey, stranger things have happened.

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