NEW YORK -- Aaron Hicks, a player his manager calls one of the "more underappreciated" in baseball, was lounging Saturday afternoon, sitting comfortably in the plush leather chair in front of his locker as college football games flickered on nearby flatscreens. Editor's Picks Who can the Yankees trust in the wild-card game?

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The New York Yankees center fielder was the calm, even-keeled antithesis of the man the baseball world saw later in the day. Perhaps after his wild, emotional, clutch late-day display, the under-the-radar tag will fade just that much more, and more heads outside the Bronx will turn in his direction. After all, October and its grand stage is almost here. This is the time of year when unfamiliar names are suddenly known in households all across America.

"I mean, Aaron, when you really peel the curtain back, he's a great player," Yankees manager Aaron Boone said. "And it's been exciting to see him evolve as one of the really good players in this league."

Although he's hitting just .249, Hicks also has 26 home runs, 76 RBIs and has scored 89 runs while sporting an .837 OPS. He has been particularly dangerous the past two games, hitting a pair of home runs and scoring five runs.

Between gawking at the breakaway speed Purdue receiver Rondale Moore showed on a TV he was watching, Hicks was bantering with passersby in the Yankees' pregame clubhouse hours before New York's game against the Baltimore Orioles. One conversation revealed that on what would prove to be the biggest day of the year so far for him and his team, the 28-year-old had no idea what was at stake.

It was explained: a Yankees win, coupled with a Tampa Bay Rays loss on Saturday, and the Bronx Bombers would be playoff-bound.

Hicks, in his typically subdued manner, simply nodded and began his day.

Several hours later, after battling through a six-pitch at-bat the Yankees weren't even sure he'd finish, Hicks helped the Yankees punch their postseason ticket with a clutch RBI double.

As Hicks was racing on a newly bum ankle around second base and headed for third, baserunner Didi Gregorius was sliding in safely headfirst at home. Coming after the Rays had already fallen in Toronto, the 3-2 walk-off winner clinched New York's postseason berth, assuring it a spot in the American League wild-card game. It was the first time the Yankees clinched a playoff spot on the same day they had a walk-off homer since Alfonso Soriano hit a game-winning home run on Sept. 24, 1999. It was also Hicks' first walk-off hit as a Yankee.

"He's one of the most underrated players in the game," Boone said of Hicks. "And [he] always kind of gets overlooked with our club. You understand some of the star players we have, some of the really good players that we have.

"But Aaron, his control of the strike zone is about as good as there is out there."

Hicks, who entered play Saturday leading all of baseball in walks drawn since the All-Star break, displayed his careful eye during his pivotal 11th-inning at-bat.

After taking a first-pitch ball, he worked his way to a 1-2 count. The very next pitch he saw, an 83.7 mph slider, got rifled hard into his left ankle, fouled off as he tried to jump all over Orioles reliever Paul Fry.

The ball hit his ankle so hard that Hicks immediately hit the ground. His bat flew out of his hands. His helmet wiggled its way off his head. Flat on his stomach, Hicks took several moments to try to collect himself as Boone and athletic trainer Steve Donohue came out to check on him and help him to his feet.

"Stevie was like, 'You going to be all right after you hit this triple? You going to be able to run and get to third?'" Hicks later recounted.

His reply? "Yeah, I'll jog."

He didn't. As soon as he made contact with a 2-2 slider two pitches after blasting his ankle, Hicks began sprinting as he lined a double down the left-field line.

"It was kind of all adrenaline going from there," Hicks said.

Aaron Hicks gets hoisted high celebrating the Yankees' clinching an AL wild card. Frank Franklin II/AP Photo

That adrenaline spilled over into the Yankees' dugout, where teammates were already making their way out of it.

"Right when Hicks hit it, we were all yelling, 'It's over. It's over,'" right fielder Aaron Judge said.

At first base, Gregorius took off. As he passed second, third-base coach Phil Nevin was waving him home. Did Hicks believe his teammate was going to score, though?

"He better. I hit it right down the line, you've got to go," Hicks said.

As soon as Gregorius came up from his slide, extending his arms out wide, Hicks flipped a switch. He was calm and even keel no more. He pumped his arms. He yelled in excitement. He ran from teammates who chased after him and followed Gregorius' lead in celebrating the walk-off hit.

Sometime during the on-field celebration, Hicks got mobbed in the middle of a jumping group of Yankees. Someone accidentally ripped off the silver chain around his neck. Eventually, speedy utility player Tyler Wade grabbed Hicks, helping to rip open his jersey.

Minutes later, the celebration continued in the Yankees' clubhouse, where the likes of Drake and Cardi B were blasted on speakers at decibel-rattling levels, champagne was shaken and poured, hugs were shared and bottle corks were saved.

Clearly, Hicks now knew he was heading to the postseason for the second straight time.

"That's the whole point of spring training is to get to this point in the year, where you're fighting for something," said Hicks, who reported postgame X-rays on his ankle came back negative.

The Yankees are well aware of how that fight continues. After reveling in Saturday's fun, the task of keeping the wild-card game in the Bronx is at hand. With their wild-card lead over the Oakland Athletics at only two games, the Yankees are still in must-win territory for the remaining eight games of the season.

"Every single time we get a chance to go to the postseason, it's a blessing. It's a lot of hard work; top to bottom in this organization," Judge said. "But we're not done yet. This is just the first step. We've just got to continue to keep working, and playing through October."

Maybe more of the baseball world will now know about at least one relatively unknown player who could make a big difference in keeping the Yankees' postseason dreams alive.