NEW YORK - Luis Severino opened with a 97 mph fastball on the low, inside corner of the plate, and Alcides Escobar drove it deep to center field.
Jacoby Ellsbury sprinted 107 feet, raised his glove above his head and snagged the ball as his head jarred into the wall. He landed on his back, toppled head over heels to the warning track but held on.
"It set the tone of the game. Escobar is standing on third or it's 1-0 if it comes out of his glove," said left fielder Brett Gardner, who ran over to comfort his New York Yankees teammate.
Ellsbury left after the first inning with a concussion and sprained neck that sent him to the disabled list. Severino allowed four hits over eight innings in his finest big league start, a 3-0 win against the Kansas City Royals on Wednesday night that opened a season-high 21/2-game AL East lead.
"Not too many people in the game make that play," right fielder Aaron Judge said. "I don't know how he held onto that ball. He hit that fence pretty hard."
Yankees manager Joe Girardi and head athletic trainer Steve Donohue spoke with Ellsbury during a 90-second delay, with Girardi removing the centerfielder's cap while they looked in the outfielder's eyes.
"He felt like it was his neck that was bothering him a little bit. Nothing to do with his head. It was more like a whiplash," Girardi said.
Donohue talked to Ellsbury at the end of the half inning, and the Yankees decided to remove the 33-year-old from the game. Doctors then determined Ellsbury sustained a concussion.
"Obviously we're going to miss him for a while now," Girardi said. "He plays hard."
Ellsbury ran face first into the wall May 1 catching a fly by Toronto's Ryan Goins, and he missed four starts.
Didi Gregorius homered against Jason Hammel (1-6) leading off the third inning, Gregorius' seventh hit in a span of 12 at-bats. New York tacked on runs with Matt Holliday's sacrifice fly in the sixth and Gardner's RBI single over a drawn-in infield in the seventh.
His fastball reaching 99 mph, Severino (3-2) allowed four hits in eight innings, struck out seven, walked one and threw a career-high 114 pitches. Severino, who lowered his ERA to 3.11, had been 0-1 in four outings since beating Boston on April 26.
"He's pitching the way that we've thought he was capable of pitching," Girardi said.
In a sign of maturity, Servino froze Eric Hosmer with a 3-2 changeup for a strikeout that ended the fourth with a runner on.
Dellin Betances, closing while Aroldis Chapman is on the disabled list, struck out the side in a perfect ninth for his fourth save as the Royals were shut out for a major league-high fifth time.
Notes: Royals LF Alex Gordon went 1-for-3 with two strikeouts after missing three games for the birth of daughter Joey Lynn. Royals RHP Nate Karns was put on the 10-day DL because of nerve irritation in his pitching arm, a move retroactive to Sunday. RHP Masahiro Tanaka (5-3), who has allowed 14 runs and seven homers in 42/3 innings in his last two starts, starts for New York in today's series finale. RHP Miguel Almonte makes his first big league start for the Royals following nine relief appearances two years ago.