as a starter after his previous seasons in the bullpen made him one of the Yankees' biggest surprises in 1977. He helped lead the Yankees to a World Series championship. In 1978, Guidry posted a career year that has been described as the all-time best season by a Yankees pitcher. Against the California Angels on June 17, he struck out a Yankee-record 18 batters. Guidry's 18-strikeout performance is usually cited as the launching pad of the Yankee Stadium tradition of fans standing and clapping for a strikeout with two strikes on the opposing batter. For the season, Guidry went 25–3, setting the all-time mark for winning percentage by a pitcher with at least twenty wins. He led the league with a 1.74 ERA, an .893 winning percentage, nine shutouts, and 248 strikeouts. Guidry's success in 1978 was due in large part to his mastery of the slider. His 248 strikeouts set a Yankees' franchise record for most strikeouts by a pitcher in a single season, a record that stood until 2022 when Gerrit Cole recorded 257 strikeouts. Guidry's 25th win of the 1978 regular season was his most significant, as it came in the Yankees' 5–4 win over the Boston Red Sox in a one-game playoff at Fenway Park in Boston to determine the American League East division winner. The game is best known for Bucky Dent's seventh-inning, three-run home run that gave the Yankees a 3–2 lead. Later that month, the Yankees again won the World Series over the Los Angeles Dodgers. Guidry won the 1978 American League Cy Young Award unanimously. He also finished second in the American League Most Valuable Player voting to Boston Red Sox slugger Jim Rice. In addition, Guidry was named The Sporting News AL Pitcher and Major League Player of the Year. Had he not taken the loss in Toronto on September 20, when his record at the time was 22-2, he would have become the first (and to date, only), pitcher ever with at least a .900 winning percentage, and at least 20 wins in a season. Ie…the first 20-game winner, to also lose fewer than three games. Guidry was named to the American League All-Star Team in 1978, 1979, 1982, and 1983. Known as an excellent fielder, Guidry won a Gold Glove each year from 1982 through 1986. In 1984, Guidry won the Roberto Clemente Award, given annually to the Major