They call these the dog days of summer and of the MLB season, but that's only bad if you're one of those strange people who doesn't like dogs. Here are five compelling plot points for you -- or your dog -- to chew on this weekend in MLB:
1. We shall overcome? The Nationals and Cubs were both good bets to win their divisions in 2018 and perhaps have a rematch of that captivating Division Series they staged last fall. But both clubs have been beset by big setbacks this season.
For Washington, Bryce Harper's had a weird year (though he's surged in the second half, much to the chagrin of those who like to tell you the Home Run Derby ruins swings), and injury issues affecting the likes of Daniel Murphy, Anthony Rendon and Adam Eaton have made keeping the regular eight on the field a struggle. For Chicago, the additions of Yu Darvish and Tyler Chatwood to the rotation have been net negatives, and the continued absence of Kristopher Bryant and closer Brandon Morrow hasn't helped, either.
The difference, you might have noticed, is that the Cubs have overcome their adversity to put themselves back atop the Brewers and the rest of the National League Central, while the Nats are still trying to re-assert themselves in an East race paced by the upstart Phillies and Braves.
So what looms this weekend at Wrigley Field is yet another stern test of the Nats' ability, in a season that has been full of them. It'll be Jeremy Hellickson opposite Kyle Hendricks in this afternoon's 2:20 p.m. ET opener, Tanner Roark vs. Jonathan Lester on Saturday at 4:05 p.m. and -- the really fun one -- Max Scherzer opposite a revitalized Cole Hamels at 8:05 p.m. on ESPN's Sunday Night Baseball.

2. Eov-olution: The Boston Red Sox, marching their way toward an AL East title and maybe even threatening the single-season wins record, already had one of the game's best starting pitchers. They might very well have made one of its shrewdest starting-pitching Deadline pickups.
When the Sox face the Orioles this weekend at Camden Yards, the four-game set, which includes a Saturday doubleheader, will feature Nathan Eovaldi in tonight's 7:05 p.m. opener and Chris Sale in Sunday's 1:05 p.m. series finale.
Sale's greatness is, by this point, well established. But Sunday will be a big day for him, as he's returning from a DL stint with mild inflammation in his shoulder. With a league-best 2.04 ERA and 216 ERA+ through 22 starts, Sale is trying to finish this season strong, not just for a Boston team running away with the AL East but for himself, as he's in good position to win his first AL Cy Young Award (he's finished in the top six each of the last six years and was the runner-up to Corey Kluber last year).
Eovaldi's allure is a little more on the subtle side, because he was a relatively low-profile trade pickup from the Rays prior to this year's non-waiver Trade Deadline. But he's developed a cutter that he's learned to pair properly with his mid-90s fastball to induce weak contact and post an invisible 0.00 ERA in his first 15 innings with the Red Sox.

3. Skilled Carpenter: On May 15, in the Cardinals' 4-1 loss to the Twins, Matt Carpenter went 0-for-4 with two strikeouts. At that moment, he was 140 plate appearances into his 2018 season, and that's generally considered a large enough statistical sample to get a read into a guy's season.
Here's what Carpenter's season looked like that day: He was batting .140 with a .558 OPS.
And here's what it looks like today: He's hitting .281 with a .991 OPS.
Any conversation about the NL MVP race has to include -- if not begin with -- Carpenter. He's leading the league not just in that OPS mark but in homers (31), FanGraphs' WAR (4.9) and in weighted runs created plus (161). In fact, he could become the first player in modern baseball history to lead his league in homers while batting predominantly from the leadoff spot.
Not only has he turned his own season around, he's powered the Cardinals -- who canned their manager and sold off assets prior to the non-waiver Trade Deadline -- back into relevance in the NL standings, where they are just 3 1/2 games back of a Wild Card spot. They've won four straight series entering their in-state Interleague affair in Kansas City, beginning tonight at 8:15 p.m. After this weekend, their schedule tightens up considerably -- Nationals, Brewers, Dodgers, Rockies, Pirates. But maybe they can hang in there if Carpenter keeps crafting big hits.

4. M's need W's: The Mariners went from being one of baseball's feel-good stories in the first half to experiencing great difficulty in the second. And it's only going to get more difficult from here. The M's have arguably the most challenging remaining schedule among MLB contenders. This weekend's four-game set in Houston -- which began with Seattle's 8-6 victory on Thursday -- marks the beginning of a 16-game stretch against the Astros, Dodgers and D-backs.
While Seattle survived early in the year on a remarkable record in one-run games, their run differential has been lopsided in favor of their opponents going back to the beginning of July. The Seattle rotation -- and most notably former ace Felix Hernandez (8.37 ERA in his last five starts, all of which were Mariners losses) -- has sprung a leak. But perhaps Mike Leake can propel them toward victory against Gerrit Cole and the 'Stros, who are expected to return Carlos Correa to the lineup tonight (8:10 p.m.).
The A's have surprisingly surged past Seattle, and the Mariners' stretch-run response -- particularly with the weight of the longest postseason drought in North American professional sports (16 seasons) bearing down on them -- will be fascinating to watch.

5. Modeling Clay: Though the Dodgers and D-backs are neck and neck in the NL West at the moment, FanGraphs is, as of this writing, giving the Dodgers a 72.5 percent chance to win the division. That's certainly not a binding forecast, but it's a window into what at least one objective analysis thinks of the Dodgers' depth relative to that of their division foes.
So for Arizona, it's important to create separation wherever possible. While the Dodgers continue a difficult assignment with another NL West contender -- the Rockies -- at Coors Field this weekend, the D-backs begin a stretch of 11 straight games against sub-.500 squads.
Of course, strength of schedule can often prove meaningless in a sport like baseball, but at least the D-backs have a pretty good option on the mound for them tonight when they open a three-game series in Cincinnati. Few were expecting Clay Buchholz to be a relevant contributor to a contender in the year 2018 (he hadn't had a season in which he posted an ERA+ above league average since 2015), but here we are. Buchholz has made 10 starts for Arizona and contributed a 2.68 ERA and 163 ERA+. He's proven he can still spin and spot an effective curve and deliver meaningful innings.
Buchholz is having the kind of year no computer could have projected. And for a club looking to defy projections and slay an established NL West giant, that's important.