"It was good," said Mattingly. "He threw the ball where he wanted. That's the main thing I watch a lot, the catcher's glove, and that gives a good indication."
That catcher, starter A.J. Ellis, echoed the manager's enthusiasm about the 40-pitch session.
"It was really good," said Ellis. "His fastball had command on both sides and the ball came out really well, with life to it. He has an easy, calm motion. He wasn't trying to impress the first time out, like some guys, and overthrow. He knew what he wanted to do and executed."
It was only the first bullpen of Spring Training, but the Dodgers did shell out $61.7 million for the left-hander -- a $25.7 million posting fee to his Korean club and a $36 million, six-year contract to Ryu –- to make him the first professional from Korea to go directly into the Major Leagues.
"I felt good with the fastball," Ryu said through an interpreter. "It's just the first day, so I took it really slow. My curveball isn't there yet. The changeup was satisfactory. Considering the time that I haven't pitched, I'm satisfied with how I did."
In his first workout Wednesday, Ryu looked out of shape in running drills. To further underscore the conditioning work ahead, he was put in the thoroughbred runners group on Thursday that included Clayton Kershaw.
"Other players don't listen to the trainer," Ryu said. "The trainer says 35 seconds, why do they run in 26 seconds? I run in 35 seconds. Other people say I'm not in shape. There are two different shapes, one for fitness, one for throwing the ball.
Mattingly tried to put Ryu's conditioning in perspective.
"You can't run it across the plate," he said. "But you've got to get in shape. He's got to work. The fact that he pushed early, I like."
Korean baseball uses a slower-paced conditioning schedule, so this is the most immediate adjustment the left-hander must make. But the fact that he's left-handed is the best example of his ability to adjust.
As the story goes, Ryu is a natural right-hander. But the first baseball glove he was given by his father was a left-hander's glove for his right hand, so Ryu taught himself to throw left-handed. When he bats, it's right-handed.
He has already shown advanced clubhouse decorum by requesting to handle the questions of two dozen Korean media outside the clubhouse, so those sessions do not infringe of the privacy and space of locker neighbors Chris Capuano and Josh Beckett.
"He's a superstar in Korea, but he's sensitive to the feelings of his teammates and does not want to do anything unacceptable," said Sun-Hoon Lee of Korean network SBS. "He's very humble and humorous. If he learns English, he'll be a very fun guy. He looks lazy, but he's not."
Pitching coach Rick Honeycutt said that in addition to displaying fastball command, Ryu had a "plus-plus changeup" that Ellis said had "a lot of movement and arm-side run."
"I would sign him myself," said Honeycutt. "To have command of four pitches at that age is highly unusual. He seems to have a good idea of what he wants to do. We know the hitters better than he does, so what we can help him with is pitch selection."
Ellis said the club sent him video of three Ryu starts after he signed so the catcher could study motion and pitch sequence. What they didn't send him was a Rosetta Stone class in Korean.
"Maybe I'll get some key phrases and put them on my wrist like a quarterback," he said.
That would have come in handy when Ellis was surrounded by the Korean media coming off the field.
"Never experienced anything like that before," he said. "That was cool."
Some emphasis for Ryu has been placed on batting -- which he hasn't done in seven years -- and developing pickoff moves that won't be called balks. He spent a few minutes hitting off a tee with hitting coach Mark McGwire, who suggested Ryu stand more upright.