McNally made his major league debut with the Orioles in 1962. Over the next few years, he developed into a reliable starter, known for his control and ability to keep hitters off balance. By 1965, he had secured a regular spot in the Orioles' rotation, and his performance began to draw attention. In 1966, McNally played a crucial role in helping the Orioles capture their first World Series title. He pitched a shutout in Game 4 against the Los Angeles Dodgers, sealing the championship for Baltimore.
The late 1960s and early 1970s marked the peak of McNally's career. He was part of a dominant Orioles pitching staff that included Jim Palmer, Mike Cuellar, and Pat Dobson. This quartet became known as one of the best rotations in baseball history. McNally's consistency on the mound was a key factor in the Orioles' success during this period. He won 20 or more games in four consecutive seasons from 1968 to 1971, a testament to his durability and skill.
In 1968, McNally posted a 22-10 record with a 1.95 ERA, earning him a spot on the American League All-Star team. The following year, he continued his strong performance, helping the Orioles reach the World Series again. Although the team fell to the New York Mets, McNally's efforts did not go unnoticed. He was named an All-Star once more in 1970 and 1971, further solidifying his reputation as one of the league's top pitchers.
McNally's prowess was not limited to the regular season. He excelled in postseason play, contributing significantly to the Orioles' World Series victories in 1966 and 1970. In the 1970 World Series against the Cincinnati Reds, McNally achieved a rare feat by hitting a grand slam in Game 3, showcasing his abilities as a hitter as well as a pitcher. This made him the first pitcher in World Series history to hit a grand slam.
As the 1970s progressed, McNally continued to be a valuable asset for the Orioles. However, injuries began to take a toll on his performance. In 1974, he was traded to the Montreal Expos, where he played his final season in 1975. Despite a decline in his performance, McNally's career statistics remained impressive. He finished with a 184-119 win-loss record, a 3.24 ERA, and 1,512 strikeouts.
Beyond his on-field achievements, McNally played a significant role in baseball history off the field. He was one of the players involved in the landmark Seitz decision, which led to the establishment of free agency in Major League Baseball. Alongside Andy Messersmith, McNally challenged the reserve clause, which bound players to their teams indefinitely. The ruling in their favor in 1975 paved the way for modern free agency, fundamentally changing the landscape of professional baseball.
After retiring from baseball, McNally returned to his hometown of Billings, Montana, where he lived a quiet life away from the spotlight.
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