Lucas Giolito Showed Ace-Level Stuff in His Major League Debut

The top pitching prospect in baseball flashed some impressive stuff in a rain-shortened MLB debut Tuesday. How good was he?

Rain, rain, go away. Come again another day so that baseball's top pitching prospect Lucas Giolito can come out and play and destroy the opposing team all day.

The Washington Nationals got their first glimpse of their future staff ace against the New York Mets on Tuesday, and it was exactly what they were hoping for. The 21-year-old fireballer only went four innings thanks to an hour and a half rain delay, but in those four innings Giolito showed why ESPN's Keith Law labeled him the best prospect in all of baseball.

That was Giolito's first career strikeout, and the only one he would get against New York. But otherwise, he cruised until rain cut short his MLB debut. He allowed just one hit and two walks in those four innings and threw 29 of his 45 pitches for strikes.

Giolito features a fastball that reached 96 miles per hour in his debut with an 86-mile-per-hour changeup that just shouldn't be allowed. He flashed all four of his pitches in his brief debut, with a two-seamer that moves and a curveball that is a true swing-and-miss pitch.

And like Noah Syndergaard, the extension Giolito gets on his pitches makes his fastball appear that much faster to opposing hitters, giving them a reaction time of 0.38 seconds, according to Stat Cast's Mike Petriello.

That's right around where Syndergaard, Dellin Betances and Craig Kimbrel tend to be, and slightly behind the 0.37 seconds Aroldis Chapman gives hitters to make up their minds whether to swing (it's important to note that Petriello's numbers come from the extremely small sample size of two innings thrown at last year's Futures Game).

Unfortunately, rain prevented everyone from seeing the rest of his arsenal on Tuesday, but judging by his time in the minors, it's pretty clear he could be a real difference-maker in the Nationals rotation this season.

In 14 starts at AA this season (71 innings pitched), he posted a 3.17 ERA, striking out 9.1 batters per nine. His control was an issue, walking 4.3 per nine innings, and throughout his minor league career, he's allowed 3.1 bases on balls per nine innings, something he'll need to work on in the Majors.

Giolito was called up to the Majors to replace Stephen Strasburg in the rotation, who is on the disabled list with inflammation in his upper back. And Giolito is the reason the Nationals were content to let Jordan Zimmermann leave via free agency this year, giving Washington a rotation for the future that is stacked with Strasburg, Giolito, and Max Scherzer, three right-handers who miss a ton of bats.

The young right-hander was only able to show a brief glimpse of his arsenal against the Mets, but if he sticks in the rotation after Strasburg returns, it's going to be a lot of fun watching the Nats' future ace roll through the rest of MLB.