In his first Major League season, went 5-3 with a 2.89 ERA (62.1IP, 53H, 21R/20ER, 22BB, 56K) in 11 starts...recorded a 0.7 WAR (FanGraphs), a 4.37 FIP and 3.72 xFIP...held opponents to a .229 (53-for-231, 9HR) batting average; LH .244 (30-for-123, 3HR), RH .213 (23-for-108, 6HR)...the team was 6-5 in his 11 starts...Was just the fourth pitcher in Yankees history to record at least five wins and post an ERA of 3.00-or-lower in his age-21 season or younger, joining Whitey Ford (1950), Hank Thormahlen (1918) and Ray Keating (1914)...since 2009, only four other Major League pitchers have accomplished that feat: Jose Fernandez (2013), Madison Bumgarner (2010), Stephen Strasburg (2010) and Clayton Kershaw (2009)...was the first AL starting pitcher to do so since the Royals' Bret Saberhagen (20-6, 2.87) won the AL Cy Young Award as a 21-year-old in 1985...His 2.89 ERA was seventh-lowest in the AL from 8/1 through the end of the season (min. 60.0IP)...had the lowest rookie ERA in the Majors in 2015 (min. 60.0IP) and lowest among rookie starting pitchers...Went 3-2 with a 2.04 ERA (35.1IP, 8ER) and 34K in his first six career starts...was the first Yankees pitcher since 1914 to record at least 30K and an ERA as low as 2.04 in his first six career games...his 2.04 ERA was the lowest by a Yankees pitcher through six career appearances (min. 30.0IP) since Bob Porterfield had a 1.94 ERA (46.1IP, 10ER) in his first six career games (two starts) in 1948...Was the fifth Yankees pitcher since 1914 to pitch at least 5.0IP while allowing 3R-or-fewer in each of his first six career games, joining Masahiro Tanaka (2014), Scott Kamieniecki (1991), Dave Righetti (1979-81) and Cliff Markle (1915-16)...was just the second Yankees pitcher since 1914 to pitch at least 5.0IP while allowing 3R-or-fewer in each of his first three career games, all starts, and not earn a single win (also Dave Righetti, 9/16-27/79)...Posted three consecutive starts with at least 6.0IP and 1R-or-fewer from 8/22-9/4, the first Yankees pitcher to pitch at least 6.0IP and allow 1R-or-fewer in three consecutive starts within his first six career games since Bob Porterfield from 8/17-25/48...had a 16.0-inning scoreless streak from 8/22-9/4...Led all Major League rookies (min. 25.0IP) with a 2.17 ERA (29.0IP, 7ER) in August...was tied for seventh with 29K...his .200 opponents' BA (21-for-105) was tied for the lowest among AL rookies and tied for second-lowest among all rookies...ranked ninth among all AL pitchers in ERA in August...His 56 strikeouts were the sixth-most by a Yankees pitcher through his first 11 career games since 1914 (Masahiro Tanaka-88, Orlando Hernandez-72, Al Leiter-69, Dave Righetti-64, Shane Greene-57)...caught Xander Bogaerts looking in the first inning of his debut on 8/5 vs. Boston for his first career strikeout... Recorded a quality start in 8-of-11 starts...had five straight QS from 8/11-9/4, just the 10th Yankees pitcher since 1914 with a five-start QS streak within his first six career games...allowed 2R-or-fewer in 8-of-11 starts...was the first Yankees pitcher in franchise history to allow 2R-or-fewer in eight starts within his first 10 career games...Per FanGraphs, his fastball averaged 95.3mph, fifth-fastest among MLB starters who threw at least 50.0IP...Went 3-2 with a 3.16 ERA (25.2IP, 9ER) in five home starts...allowed 1ER-or-fewer in 4-of-5 starts...was the first Yankees starter to allow 1ER-or-fewer in each of his first three starts at the current Yankee Stadium...three visiting pitchers have also done it: Carlos Carrasco, Felix Hernandez and Brian Matusz...Made his Major League debut at 21 years, 166 days old on 8/5 vs. Boston and took the loss in the Yankees' 2-1 defeat (5.0IP, 2H, 2R/1ER, 0BB, 7K, 1HR)...caught Xander Boegarts looking for his first career strikeout...was the youngest pitcher to make a start in the Majors in 2015 and the youngest Yankees pitcher to start a game since Phil Hughes was 21 years, 95 days old in his final start of 2007...became the first pitcher in AL history with 2H-or-fewer, no walks and at least 7K in his Major League debut...was the sixth MLB pitcher (third starter) to do it in the Modern Era (since 1900), joining five NL pitchers: Atlanta's Manny Banuelos (5.2IP, 2H, 0BB, 7K on 7/2/15 vs. Washington); Arizona's Max Scherzer (4.1IP, 0H, 0BB, 7K on 4/29/08 vs. Houston); Cincinnati's Johnny Cueto (7.0IP, 1H, 0BB, 10K on 4/3/08 vs. Arizona); Los Angeles-NL's Pete Richert (3.1IP, 0H, 0BB, 7K on 4/12/62 vs. Cincinnati); and the Milwaukee Braves' Don McMahon (4.0IP, 2H, 0BB, 7K on 6/30/57-G2 vs. Pittsburgh)...was the third pitcher in Yankees history to record at least 7K and no walks in his Major League debut, joining Masahiro Tanaka (7.0IP, 0BB, 8K on 4/4/14 at Toronto) and Rich Beck (7.0IP, 0BB, 8K on 9/14/65 at Washington-AL)...was the first Yankees starter since 1914 to take a loss while throwing at least 5.0IP and allowing two baserunners-or-fewer (via H/BB/HP)...was just the third Yankees pitcher over the last 51 seasons (since 1965) to make his Major League debut in a start vs. the Red Sox, joining LHP Randy Keisler on 9/10/00 at Boston and RHP Sam Militello on 8/9/92 vs. Boston...was one of 18 Yankees to make their Major League debuts in 2015 but the only one to do so as a starting pitcher...Debuted in the same series as Red Sox LHP Henry Owens (8/4/15), as the two became just the second pair of Yankees and Red Sox pitchers since 1914 to make their MLB debuts as starting pitchers in the same series, joining Red Sox RHP Jim Bagby (4/18/38 vs. New York) and Yankees RHP Atley Donald (4/21/38 at Boston)...Recorded a career-high 9K on 8/16 at Toronto (third career start)...became just the 10th Yankees pitcher since 1914 to record at least 9K in one of his first three Major League games...at 21 years, 177 days old, was the second-youngest Yankees pitcher since 1914 to record 9K-or-more in a game, also Ray Keating (20 years, 302 days), who had 9K on 5/19/1914 vs. St. Louis-AL...in that span, only four Yankees pitchers had games with at least 9K prior to turning 22: Severino, Al Leiter (21 years, 337 days on 9/25/87 at Baltimore-10K), Al Downing (2x: 21 years, 352 days on 6/15/63 vs. Detroit-9K; 21 years, 347 days on 6/10/63 at Washington-AL-9K) and Keating...Earned his first Major League win on 8/22 vs. Cleveland (6.0IP, 3H, 1ER, 1HR, 4BB, 6K, 1HR)...Recorded his first career scoreless start in 8/29 win at Atlanta (6.0IP, 4H, 0R, 3BB, 5K)...at 21 years, 190 days, was just the second Yankees pitcher since 1970 to throw at least 6.0 shutout innings in a game before turning 22 years old (Phil Hughes, 6.1IP, 0H, 0R on 5/1/07 at Texas-20 years, 311 days)...In his final regular season start, threw a career-high 7.0IP but took a no-decision on 10/3-G2 at Baltimore (5H, 3ER, 0BB, 6K, 2HR)...at 21 years, 225 days, was the youngest Yankees pitcher with a start of at least 7.0IP and no walks since Stan Bahnsen on 9/22/66 vs. Chicago-AL (7.0IP, 4H, 2ER, 0BB, 6K)...Went 9-2 with a 2.45 ERA (99.1IP, 72H, 35R/27ER, 27BB, 98K) in 19 starts between Double-A Trenton and Triple-A Scranton/Wilkes-Barre...opposing batters hit just .201 (72-for-359)...allowed just 2HR while facing 396 batters...did not allow a HR in his final 71.1IP... was 7-0 with a 1.91 ERA (61.1IP, 13ER) in 11 starts with Scranton/WB following a 5/30 promotion from Trenton...during his Triple-A stint (5/31-8/5), led qualifying Triple-A pitchers in winning pct., tied for the lead in wins and ranked fourth in ERA (min. 50.0IP)...went 2-2 with a 3.32 ERA (38.0IP, 14ER) in eight starts with Trenton...after the season, was named to Baseball America's 2015 Triple-A Post-Season All-Star Team...In Baseball America's 2015 "Best Tools" survey, was tabbed with the "Best Fastball" in both the Triple-A International League and Double-A Eastern League and the "Best Breaking Pitch" in the International League, as voted on by league managers and coaches...was named an MiLB.com Organization All-Star... Attended spring training as a non-roster invitee, posting a 6.75 ERA (2.2IP, 6H, 3R/2ER, 1BB, 5K) in two appearances.