In his start Friday against the White Sox, Clayton Kershaw allowed five runs in six innings, including two home runs. It was the second time this season Kershaw’s allowed multiple home runs in a game, already matching a career high.

Clayton Kershaw's Slider
Last 2 Seasons

Kershaw’s first home run came on an 0-2 pitch to Adam Dunn in the first inning. It was the second home run Kershaw has allowed this season on an 0-2 count; he had allowed only one such home run in his career entering 2012. Dunn now has four career home runs against Kershaw in only 13 at-bats. No other player has more than two home runs against Kershaw.

Kershaw, who’s already allowed 10 home runs in 15 starts, hadn’t allowed more than seven home runs in his first 15 starts of any season of his career. One reason for the increase in home runs might be the relative lack of effectiveness of his slider.

A season ago, Kershaw’s slider ranked among the best pitches in baseball. His 138 strikeouts with the pitch led the majors, and he allowed just three home runs with it. Opponents hit .121 against it.

This year, Kershaw’s slider, while still an above-average offering, has not been quite as dominant as it was a year ago. He’s already allowed five home runs with his slider, and he’s averaging almost a strikeout and a half less per start with it, compared to a year ago. At least some of the difference in effectiveness can be explained by how he’s using the pitch; he’s using his slider this year more often before two strikes than last year and less often with two strikes, when he’s looking to put hitters away.

Thursday’s start against Oakland is a good example of this. Despite throwing 25 sliders, Kershaw did not strike out an Athletics hitter with the pitch. It was Kershaw’s second start in the last two season in which he did not strike out a hitter with his slider; the other was last season against St. Louis, a start in which Kershaw threw the pitch just four times.

Against the Athletics, 21 percent of Kershaw’s pitches before two strikes were sliders. When he got to two strikes, 24 percent of his pitches were sliders. For the season, those numbers are at 18 percent and 40 percent, respectively. Although that may seem like a wide margin, consider last year. In 2011, a season in which he led the league in slider strikeouts, 13 percent of Kershaw’s pre-two-strike offerings and 46 percent of his two-strike pitches were sliders.

Even without his slider being quite as dominant as it was last year or as much of a strikeout pitch as it was last year, Kershaw has still been very effective. Thursday against Oakland, he struck out five hitters with his fastball, the second time in his last three starts in which he’s done that. He didn’t do it once in 2011. With or without his best slider, Kershaw will continue to rank among the league’s top starters, but a return to last year’s slider is key to bringing him back to last year’s dominance.

Thanks to Baseball-Reference, here are some other notes looking back on the past week for the Dodgers.

OFFENSE DOESN’T TRAVEL TO OAKLAND

The Dodgers were shut out on two hits in the first game of their three-game series before mustering only one run on three hits in each of the next two games. It’s the first time in the Live Ball Era that the Dodgers were held to three hits or fewer in three consecutive games. They’re the first team since the 1978 Rangers to be held to no more than one run and no more than three hits in three straight games.

ETHIER COOLS OFF

Andre Ethier was 4 for 21 (.190) on the week, which actually raised his June batting average to .171 from .163 entering last Friday. Of particular note are Ethier’s struggles against lefties. In 34 at-bats against southpaws this month, Ethier has four hits, no home runs, and 15 strikeouts. He’s swung and missed exactly twice as often as he’s put the ball in play against lefties in June (38 to 19).

Ethier faced White Sox lefty Jose Quintana three times Sunday, striking out swinging in each at-bat. Ethier swung and missed eight times in the game, all against Quintana, the first time in the last four seasons he’d missed on that many swings in a game. It was the first time in almost two years that the same pitcher struck Ethier out three times in a game; CC Sabathia did it on June 25, 2010.

LOSING CONTROL

Aaron Harang walked a career-high eight hitters Tuesday night, most by any pitcher since Ian Kennedy walked nine on June 26, 2010. The day before that, Kennedy's then-teammate Edwin Jackson walked eight in his no-hitter against the Rays. Jackson was also the last Dodger to walk eight, doing so on Sept. 27, 2003. Jackson allowed two hits and no runs in that start.

Harang threw 105 pitches over 3 2/3 innings. Going back to 2000, as far as pitch count numbers are complete, Harang is the first Dodgers pitcher to throw 100 pitches in an outing of less than four innings. No Dodger had walked eight hitters in a start of less than five innings since Sandy Koufax in 1955 in his first career start. Koufax walked eight over 4 2/3.

As a team, the Dodgers walked 10 hitters Tuesday, the second time this season they’ve walked at least that many (they walked 10 Padres on April 7). The Dodgers joined the Blue Jays and Rockies as the only teams to walk 10 hitters in a game twice. LA hadn’t done it since 2006, when they did it three times.