Yu Darvish on July 16, 2016

Photo credit: By Julie Fennell on Flickr (Original version) UCinternational (Crop) [CC BY 2.0 (http://creativecommons.org/licenses/by/2.0)], via Wikimedia Commons.

Yu Darvish began his Sunday start against the Astros by yielding a home run to George Springer, and four innings later, he exited the game with his worst stat line of the season. Given that Darvish entered the game with a streak of eight straight quality starts, it would seem like an overreaction to think about downgrading him for Fantasy going forward. After taking a look at Darvish’s body of work in the second half, I don’t think that’s going overboard.

When Darvish made his first post-break start on July 16, he was coming off a month-plus stay on the disabled list with neck and shoulder discomfort. That first start back was a clunker against the Cubs, but then he commenced on his quality start streak. Almost everything Darvish did during those eight games seemed to indicate that he was back to being a must-start option. He struck out 10.8 batters per nine innings and walked just 1.9 batters per nine. Those ratios backed up a 2.96 ERA.

One number that was higher than ideal was Darvish’s .178 Isolated Power allowed during that stretch. Darvish’s ground ball rate during that stretch was only 34.5 percent, and if he visited more hitter-friendly parks, it’s conceivable that Iso could have been even higher. Flyball tendencies aren’t new to Darvish, as his ground ball rate was only two percentage points higher in 2014, just before he underwent Tommy John surgery. In that season, Darvish got by with a lower-than-average 6.5 percent HR/FB ratio (per Baseball-Reference). During his quality start streak, that mark rested at 9.0 percent.

Any pitcher can go through a rough stretch with home runs, but a pattern has emerged for Darvish that suggests this may not be a short-term issue. Since coming off the DL, Darvish has cut back on his sinker usage, throwing it 16.2 percent of the time, as opposed to 29.4 percent in his three prior starts. The deemphasis of his sinker corresponded with the re-introduction of his curve, and neither trend has helped with Darvish’s ground ball rate. While his sinker has been only mildly effective at inducing grounders (43.5 percent rate, per Brooks Baseball), his curve has been far worse, with a 34.8 percent rate.

Brooksbaseball-Chart-3

According to the Dallas Morning News, Darvish relied on his curve and slider right after allowing the leadoff home run to Springer. Neither offering has been a good ground ball pitch this season, so that’s not an encouraging trend for when Darvish has trouble with his fastball.

I’m not trying to alarm owners into sitting Darvish, but other than when he first came back from Tommy John in May, I have not questioned him as someone who just stays plugged into an active rotation spot in any format. Looking ahead at the final four weeks of the Rangers’ schedule, I see two potentially worrisome matchups. In Week 24, Darvish lines up to face the Astros again, but this time at Minute Maid Park, which is more amenable to home runs than Globe Life Park in Arlington. In Week 26, he will likely oppose the Brewers, who have mashed 40 homers over the last 30 days with a .188 Iso. That could be the first of a two-start week…or maybe not, depending on how manager Jeff Banister wants to arrange his rotation heading into the playoffs.

This week, Darvish visits the Angels, and neither the opponent nor the ballpark poses a clear threat to a flyball-prone pitcher. If he struggles again, it may be time to make start/sit decisions for Darvish on a game-by-game basis.