5 questions we still have about Roki Sasaki after resurgent Minor League outing

While the Los Angeles Dodgers are fighting tooth and nail to stay atop the NL West down the stretch, one of their biggest offseason acquisitions is stuck in Triple-A. Roki Sasaki's first pass at starting in the Majors was far bumpier than anyone expected, culminating in a shoulder issue that landed him on the IL back in May. He began a rehab stint with Oklahoma City last month, but the persistent fastball velocity issues that dogged him at the start of the season were still present.

It was enough to have fans wondering whether they'd been sold a bill of goods, or whether Sasaki would ever again reach the heights he saw as a phenom in Japan. Not even manager Dave Roberts could hide his discouragement. But on Tuesday night, we finally saw something resembling the old Roki again:

Sasaki was suddenly back in the high 90s with his fastball, even cracking triple digits multiple times. And that velo led to far more swing and miss than he'd ever shown before as a member of the Dodgers: He racked up 16 whiffs on the night, with eight strikeouts in just 4.2 innings of work.

And a look under the hood showed real reason for optimism beyond the radar gun. This is the sort of profile we expected to see when he came to the States last winter: a crackling fastball that set up a ridiculous set of offspeed pitches.

All of which has Dodgers fans daring to dream again. And you can't really blame them: We know how special Sasaki can be at full throttle. But it is just one start, against a Minor League lineup no less. There's still a lot that we don't know about the righty's short- and long-term future, so let's dive in.

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Is the velocity here to stay?

This is the big one, after which everything else flows. It's a tremendously encouraging sign that Sasaki's velocity is back up in the high 90s, the sort of heat that first made him a star but that he's had a hard time recapturing even going back to his final season in Japan. The shape on the righty's fastball has always been suboptimal; he doesn't get the sort of ride that can fool hitters, so he needs the extra juice in order to miss bats and set up his tremendous offspeed stuff. Sasaki at 98-100 is a far, far different proposition from Sasaki at 94-95.

But at this point, we need to see it for more than one outing. Again, this is a problem that predates him coming to the States in the first place — one of the biggest factors in his free agency last winter was which team could come up with the best plan to get his velocity back on track. The fact that his shoulder is feeling healthy enough to get back up toward triple digits is great, but what will it look like in his next outing? And will it sustain across a full season?

Does he have the stamina to start?

At this point, it's fair to raise durability concerns with Sasaki. It's not the biggest frame at 6-foot-2 and just 187 pounds, and we've yet to see him successfully approach something that approximates the workload of a Major League starter. This is the same guy who was recommended for Tommy John surgery when he was 18, and while he opted against it and kept on pitching, he also dealt with arm discomfort during his final season in Japan.

The righty has yet to throw even 130 innings in a season, and that was with an NPB schedule that allows pitchers an extra day of rest. He threw just 34.1 innings for L.A. before landing on the shelf with what was eventually diagnosed as a shoulder impingement. That's ... a lot of red flags before your 24th birthday, to say the least.

Of course, every pitcher is an injury risk until they're not. Maybe Sasaki is perfectly capable of throwing 180 innings in a season. But this whole situation is a lot more complicated than just finding his old stuff.

Will the command ever stabilize?

One of the most alarming things about Sasaki's MLB debut was his inability to find the strike zone. This is a guy who walked just 88 batters across 394.2 NPB innings. Over his first eight starts with the Dodgers, he walked 22 — a 5.8 BB/9 that has persisted down in the Minors. Even in his bounce-back start on Tuesday night, he walked four in just 4.2 innings of work.

Of course, most of those walks came towards the end of his outing, when his stamina was clearly fading — hardly the biggest sin for a guy coming off an extended IL stint due to a shoulder issue. And the command could well be related to the decline in stuff: Without his plus velocity, Sasaki was a bit more skittish about challenging hitters, leading to a lot more nibbling than we saw in Japan.

Stil, it's something that bears monitoring. If Sasaki can't overwhelm big-league hitters the way he did in NPB, he'll need to be a lot more precise in order to turn a lineup over multiple times.

What role might he be able to play for the Dodgers this year?

There's no question that the Dodgers still intend on Sasaki starting long-term, as well they should. But that still leaves the matter of 2025: If this is a sign that Sasaki's feeling healthy and confident enough to return to the Majors, does Los Angeles have room for him?

Right now, the answer would appear to be "no," at least in the rotation. Yoshinobu Yamamoto, Blake Snell, Tyler Glasnow, Shohei Ohtani, Clayton Kershaw and Emmet Sheehan have all been too good, and that's a six-man rotation already. Which begs the question: Might the Dodgers have room for him in their beleaguered bullpen?

Roberts is playing coy for now, telling MLB.com that "anything's possible".

"I know Roki is anxious to get back here. I know he wants to contribute," he said. "Like I said last week, guys are pitching well as far as starters. So we just got to see where he fits in, and we'll have that conversation as an organization."

Of course, it's not quite so simple as just asking Sasaki to do something he's never done before in the heat of a pennant race. We have no idea how he'd take to high-leverage relief work. That said, maybe a long relief role could be in the cards, one that would see him piggybacking with Ohtani or Kershaw to help keep them fresh down the stretch.

Is he mentally ready to return to the Majors?

I want to be very careful here: I'm not stating or implying that Sasaki is "soft," or anything like it, or that he's not cut out to pitch in the States. He's gone through a profound transition over the last few months, learning a new country and culture and language and league all on the fly while shouldering massive expectations. It's more than understandable for that to take a toll on anyone, let alone someone in his early 20s.

Still, it remains true that Sasaki was more than just physically injured by the time the Dodgers put him on the shelf — he seemed mentally and emotionally depleted. Again, there are very good reasons for that: His free agency created a nearly unprecedented frenzy of attention, and I have no idea how I would respond to struggling publicly in the face of that in the way that Sasaki did. That frenzy isn't going anywhere, though; if anything, it's about to become even more intense if he returns to the Major League roster on the verge of the postseason.