NEW YORK -- Luis Severino bounded off the mound at Yankee Stadium on the evening of Oct. 9, a thick gold chain spilling out of his uniform top while he joyously pounded his right fist into his glove. After earning recognition as the Yankees' newest ace during the regular season, he had now backed the title up on a postseason stage.
Pumping high-velocity fastballs past the Indians' flailing lineup through seven innings that night, Severino delivered a nine-strikeout effort in Game 4 of the American League Division Series to help force a decisive showdown in Cleveland. It also offered a glimpse of what the Yankees hope is still to come from the whip-armed right-hander.
"I just worry about my game," Severino said. "I don't worry about the fans, the noises. I just try to control myself, focus on hitting the glove and make good pitches."

Severino, who will turn 24 in February and appears a safe bet to be new manager Aaron Boone's choice as the Opening Day starter, finished third in the American League Cy Young Award voting this past season after going 14-6 with a 2.98 ERA over a team-leading 31 starts.
An AL All-Star in his first full Major League season, Severino ranked third in the league in ERA, fourth in strikeouts (230), ninth in innings pitched (193 1/3) and tied for ninth in victories. His 10.71 strikeouts per nine innings were the highest such ratio in Yankees history.
"Every time I look up there, it's always 0-1, 0-2," Aaron Judge said in October. "He's never falling behind a lot of hitters. When you've got his repertoire and his stuff and you're getting ahead of guys like that, good things will happen. He just dominates hitters."
There had been some questions about Severino's future following his troublesome 2016 campaign, in which he went 0-8 with an 8.50 ERA in 11 starts but excelled out of the bullpen, compiling an 0.39 ERA in 23 1/3 innings.
"It was not something that you all of a sudden just pivot," general manager Brian Cashman said. "This guy has the potential to be an ace, and then you're going to all of a sudden just throw that out the door and say that's not the case anymore? Development involves patience, and he had to go through that process, for whatever reason."

Following that season, the Yankees sent Severino back to the Dominican Republic, instructing him to ease off on weight-lifting. Pitching coach Larry Rothschild speculated that a more lithe form would help create separation between his fastball and changeup -- the latter, a key offering that Severino had lost faith in.
"I have a lot of confidence in it now," Severino said. "I can throw my changeup in any count. That's the difference from last year."
While Severino credited Rothschild for his assistance, he also called upon outside help, scoring Hall of Famer Pedro Martinez's contact information from a mutual friend. Martinez agreed to meet Severino on several occasions at Estadio Quisqueya in Santo Domingo, where the 18-year big league vet reviewed the hurler's mechanics, mound presence and poise.
"He figured we were very similar," Martinez told Newsday. "He idolized me when I was pitching and he was a kid watching me at home. And he figured we look alike a lot and he wanted to actually correct some of the things that he was doing wrong, and I was able to help him out."
Martinez was no fan favorite in the Bronx during his playing days, but maybe the Yankees should add him to their Christmas card list. One of Martinez's lasting contributions to Severino's form was helping him throw his changeup from the same arm slot as his fastball, which made Severino's devastating slider even more of a weapon against big league hitters.
"I'm proud of the work that I did in the offseason," Severino said. "And I'm proud of myself and the team that we have."