(Sung to the tune of "Big Poppa")

It took over a decade, but the San Francisco Giants have finally reduced Dodgers' ace Clayton Kershaw to a merely mortal opponent.
(It also took injuries and a decrease in the quality of Kershaw' stuff, but we don't need to muck up the Giants' accomplishment with facts. Let's just bask in it.)

Almost from the time he entered the league in 2008, Kershaw has been crafting a Hall-of-Fame resume down at Dodger Stadium. Or wherever else his starting assignments took place. Of course, during his periods of peak invincibility, the Dodgers were either falling short in the playoffs, or falling short of the playoffs entirely while the San Francisco Giants were winning three World Series out of five.

While it's obviously true that during that stretch, Giants fans held bragging rights, we didn't quite hold all the bragging rights as long as Kershaw was running roughshod through Giants lineups while wearing a Dodgers uniform. 
I compare it to being named homecoming queen, captain of the cheer squad, and valedictorian...all the while watching your worst enemy dating your crush. Sure, you're on top. Sure, you have plenty to boast about. Sure, loads of people would kill to be in your shoes. But your nemesis is experiencing pleasure at your expense, and we just can't have that.

If the Giants were so good, it was often said, how come Kershaw got the best of them damn near every single time?
Even if you countered with the obvious "If Kershaw was so good, how does he get lit up so much in October?", the haters did have a point.

You may or may not know the early numbers. 
The Claw opened his career 14-5 against the Giants, with a sub-2 ERA. Impressive numbers, obviously, but it goes beyond that.
The 14-5 felt more like 17-2. Some years, he'd face the Giants five times and win all five. And he didn't just win—he made it look easy. No matter who the Giants batter, he'd undoubtedly be left flailing at curveballs bouncing off the plate, 10 feet in front of changeups, 10 feet behind fastballs, overmatched by sliders.

Looking back, I honestly don't know how the Giants beat Kershaw five times prior to 2015. He was dominating the whole league in those years, but he was outright embarrassing San Francisco. Even his lone career home run to date is against the Giants (served up by George Kontos). But—despite how it looks—I'm not here to talk about the past.

In recent years, Kershaw has lost a little steam off his fastball. He's battled back injuries and this year, a shoulder injury. He turned 30 in 2018. His numbers are still better than 4/5 of the league, but he's relying more on guile and experience and less on skill and talent to achieve them. While universally respected, he is no longer feared—certainly not by San Francisco, who despite overall struggles have gone 4-3 against Kershaw in his last seven starts against them (2018-19).
Tell the 2011 Giants—several of whom made up the 2019 Giants—that the Claw would, in some future period, go 1-3 against SF over seven starts. They'd be mystified at such a prospect and wonder what league rule was passed to make it possible.

Making it possible on 9/6: rookie Mauricio Dubon, who only joined the Giants (and MLB) last week. He grew up a Giants fan, so he may be aware of Kershaw's past dominance. But as a rookie, he's too green to really care or be awed, and it showed in his three-hit, three-RBI performance (which included a bomb off the fair pole).
CF Kevin Pillar knocked Kershaw out of the game in the 5th with a 12-pitch walk—cue camera catching the ace slamming and kicking something in the dugout. "I USED TO OWN THESE DOPES!" he was probably thinking. "NOW I CAN'T EVEN LAST FIVE AGAINST 'EM?"

Well, these aren't the same dopes Kershaw used to own. Can this group of Giants win the World Series? No. Can they steal a playoff spot? No. Can they finish at .500? Most likely, no. But they've proven twice this year that they can beat Clayton Kershaw, even in his home park, even with AJ Pollock ripping three home runs.

Final note: Despite the 9/6/19 loss and recent slump, Kershaw remains 23-12, 1.74 in 47 lifetime starts against the Giants, including a 2019 victory.