In 2002, Zito became one of the best pitchers in baseball.
On June 22, Zito won his 10th game of the season.
It was the earliest that an A's pitcher had reached the 10-win mark since Bob Welch got there on June 15, 1990.
Zito was named to the All-Star team for the first time in his career.
On July 18, he went 7.1 innings while giving up no runs against the Angels.
That win gave Zito a team-record 16th straight win at home.
Zito again faced the Angels in his next start and produced similar results.
He went 6.1 innings and gave up just one run.
That win gave Zito the most wins by an AL pitcher (14).
Zito would become the AL's first 15-game winner when he beat the Rangers.
On August 23, Zito recorded his 18th win of the season, giving him one more than his previous career high of 17, in a game against the Detroit Tigers.

On August 28, Zito earned his 19th win of the season against the Kansas City Royals.
However, he lost his bid for a perfect game in the sixth inning when Neifi Pérez singled with one out.
Zito gave credit to Pérez. "
I wasn't pitching to maintain a no-hitter or something", Zito said. "
I left the ball up over the middle to Pérez, and he hit it up the middle.
It was a good piece of hitting."

On September 8, Zito became the first pitcher in the AL to win 20 games when he pitched seven innings and allowed no earned runs against the Minnesota Twins. "
I'm not pitching for the Cy Young", Zito said. "
I'm pitching to get the Oakland A's into the playoffs and to the World Series."
In his next start, against the Seattle Mariners, Zito took a no-hitter into the eighth inning before John Olerud singled to leadoff the inning.
Seattle manager Lou Piniella said if he could vote for the Cy Young Award winner, "It would go to that young man who pitched for the Oakland team.
There are other deserving pitchers, but [Zito] has won 21 games and he competes well."

In his last start of the season, Zito went six innings and allowed just a run against the Texas Rangers.
In his last 10 starts, Zito went 8–0, boosting his chances of winning the AL Cy Young Award. "
Barry pitched another gem", said Oakland manager Art Howe. "
He's certainly had a Cy Young-type season.
He's just been steady all season long."

In Game 3 of the ALDS, Zito went six innings and gave up three earned runs against the Twins, earning the win.
However, the Twins defeated the Athletics in five games, making the Athletics the first team to lose the deciding game of a series three years in a row.

Zito would go on to win the AL Cy Young Award with a 23–5 record, narrowly defeating Pedro Martínez in the voting.
He led the league with 23 wins, was second in winning percentage (.821), and third in both ERA (2.75) and strikeouts (182).
Zito's 23 wins were the most by an AL left-hander since Frank Viola had 24 wins for Minnesota in 1988.
Zito also allowed a .185 average to opposing hitters, the lowest in the AL.
Martínez, who had led the AL in ERA (2.26), strikeouts (239), and winning percentage (.833), became the first pitcher since the introduction of the award to lead his league in each of the three categories and not win the award.
Zito became the first A's pitcher to win the Cy Young Award since Dennis Eckersley did it in 1992.
Zito was also named AL TSN Pitcher of the Year.
In 2002, Zito became one of the best pitchers in baseball. On June 22, Zito won his 10th game of the season. It was the earliest that an A's pitcher had reached the 10-win mark since Bob Welch got there on June 15, 1990. Zito was named to the All-Star team for the first time in his career. On July 18, he went 7.1 innings while giving up no runs against the Angels. That win gave Zito a team-record 16th straight win at home. Zito again faced the Angels in his next start and produced similar results. He went 6.1 innings and gave up just one run. That win gave Zito the most wins by an AL pitcher (14). Zito would become the AL's first 15-game winner when he beat the Rangers. On August 23, Zito recorded his 18th win of the season, giving him one more than his previous career high of 17, in a game against the Detroit Tigers.
On August 28, Zito earned his 19th win of the season against the Kansas City Royals. However, he lost his bid for a perfect game in the sixth inning when Neifi Pérez singled with one out. Zito gave credit to Pérez. "I wasn't pitching to maintain a no-hitter or something", Zito said. "I left the ball up over the middle to Pérez, and he hit it up the middle. It was a good piece of hitting."
On September 8, Zito became the first pitcher in the AL to win 20 games when he pitched seven innings and allowed no earned runs against the Minnesota Twins. "I'm not pitching for the Cy Young", Zito said. "I'm pitching to get the Oakland A's into the playoffs and to the World Series." In his next start, against the Seattle Mariners, Zito took a no-hitter into the eighth inning before John Olerud singled to leadoff the inning. Seattle manager Lou Piniella said if he could vote for the Cy Young Award winner, "It would go to that young man who pitched for the Oakland team. There are other deserving pitchers, but [Zito] has won 21 games and he competes well."
In his last start of the season, Zito went six innings and allowed just a run against the Texas Rangers. In his last 10 starts, Zito went 8–0, boosting his chances of winning the AL Cy Young Award. "Barry pitched another gem", said Oakland manager Art Howe. "He's certainly had a Cy Young-type season. He's just been steady all season long."
In Game 3 of the ALDS, Zito went six innings and gave up three earned runs against the Twins, earning the win. However, the Twins defeated the Athletics in five games, making the Athletics the first team to lose the deciding game of a series three years in a row.
Zito would go on to win the AL Cy Young Award with a 23–5 record, narrowly defeating Pedro Martínez in the voting. He led the league with 23 wins, was second in winning percentage (.821), and third in both ERA (2.75) and strikeouts (182). Zito's 23 wins were the most by an AL left-hander since Frank Viola had 24 wins for Minnesota in 1988. Zito also allowed a .185 average to opposing hitters, the lowest in the AL. Martínez, who had led the AL in ERA (2.26), strikeouts (239), and winning percentage (.833), became the first pitcher since the introduction of the award to lead his league in each of the three categories and not win the award. Zito became the first A's pitcher to win the Cy Young Award since Dennis Eckersley did it in 1992. Zito was also named AL TSN Pitcher of the Year.
Barry Zito