Hyun Jin Ryu’s Impending Sophomore Slump?

Without Masahiro Tanaka in the fold, and with the fifth starter role still up in the air, Hyun Jin Ryu‘s ability to be consistent as the Dodgers‘ #3 starter becomes all the more important to the quality and depth of the 2014 starting rotation. Since his performance will be key this year, Mark Saxon of ESPN Los Angeles wondered if the team should worry that Ryu is due for a sophomore slump.

It’s difficult to predict what pitchers will do coming off strong rookie seasons. For every Dwight Gooden, who takes a major step forward, there is a Rick Sutcliffe, who regresses dramatically.

It’s probably a bit more instructive to compare Ryu to other pitchers who came straight from foreign professional leagues, because — unlike U.S. players — they have no minor-league history with any of the hitters they’re facing. They often have been lightly scouted. It’s fair to say they own a sizeable advantage on the hitters, one which fades over time.

But again, we find mixed signals.

Ryu’s numbers — a .252 batting average on balls in play and 1.20 WHIP — suggest he could be in for a bit of a come-down in year two, as his luck was better than the average pitcher’s. On the other hand, he’s not a power pitcher and he’s not overly reliant on strikeouts. He tends to be pitch-efficient, which bodes well for his chances of giving the Dodgers consistent innings.

So, will he endure a sophomore slump? Probably, but it seems highly endurable.

As cliche as a sophomore slump sounds, there’s history to it in terms of Rookie Of The Year types who regress, and Ryu’s case is an interesting one to explore further.

In the argument Saxon is making, I’m not sure I can endorse a prediction of even an “endurable slump”. And it’s not even that I necessarily disagree, as there does figure to be a bit of regression in store for Ryu, but it’s hardly the 50/50 proposition between sophomore slump and continuing success that’s currently being juxtaposed.

For starters, if Ryu’s BABIP was .252 then that would indeed be cause for worry, because the team’s BABIP against was .291 and the league average was .294. Fortunately, Ryu’s actual BABIP was .296, making his luck in terms of batted balls quite neutral. And it’s why his peripherals led to a 3.24 FIP and 3.46 xFIP to go along with his 3.00 ERA.

That type of rock solid performance figures into all of Ryu’s 2014 projections, which have him as a dependable middle rotation guy across the board.

Hyun Jin Ryu’s 2014 Projections
Projection	IP	K/9	B/9	ERA	WAR
Steamer	189.0	7.7	2.7	3.55	2.7
PECOTA	186.0	7.1	2.2	3.39	2.1
ZiPS	182.1	7.8	2.5	3.65	2.2
Oliver	188.0	7.0	2.4	3.12	2.6

That said, the reason some regression figures to occur is because of his 78.2 LOB% (strand rate), which ranked 13th in all of the MLB among qualified pitchers, compared to the league average of 73.5%. A big part of Ryu’s ability to get out of trouble like that was predicated on him inducing double plays, as Ryu managed to generate 26 double plays in 2013, third in the MLB. But even that has a justification attached to it since the double plays stem from Ryu’s groundball rate (50.6%), which ranked him 13th in the MLB among qualified pitchers.

So while expectations should account for the fact that Ryu projects to take a tiny step back in 2014, his 2013 was due to anything but luck or a lack of adjustment time (3.57 1H FIP/2.73 2H FIP). As with any pitcher, there’s always a chance for regression or statistical quirks, but Ryu’s 2013 was legitimately solid and he cemented himself statistically as a deserving #3 starter on a first-division team. And at the end of the day, Ryu’s at least as safe a bet to stave off a down year as his rotation-mates Clayton Kershaw and Zack Greinke.