Dave McNally, 60, one of the great left-handed pitchers for the Baltimore Orioles in their glory years in the 1960s and 1970s who also made his mark in labor history when he won a landmark contract arbitration case that left him a free agent and led to the modern era of exploding salaries, died of cancer Dec. 1 in Billings, Mont.

Mr. McNally spent 14 seasons in major league baseball, all but the last of those with the Orioles. He made his debut in 1962, pitching a two-hit shutout against the Kansas City Athletics.

The savvy and cool control artist went on to win 183 more games -- while losing 119 -- with a sparkling lifetime earned run average of 3.24. Before being traded to the Montreal Expos at the end of the 1974 season, he had become a three-time all-star and had helped the Orioles win four pennants and two World Series titles.

He won 21 games with the Orioles' 1971 pennant-winning team, which included three other pitchers who won 20 games each: Jim Palmer, Pat Dobson and fellow southpaw Mike Cuellar. The only other major league team to boast four pitchers to win 20 or more games in a season was the Chicago White Sox in 1920.

Mr. McNally won 20 or more games with the Orioles four straight seasons, from 1968 to 1971. In 1970, he led the American League in victories with 24. But his best year was 1968, when he went 22-10 with a 1.95 ERA, completing 18 of his 35 starts and striking out 202 batters while walking only 55 and giving up 175 hits in 273 innings.

He was 3-2 in league championship play and 2-1 in World Series competition. In the 1966 World Series, he threw a four-hitter, outdueling the Dodgers' Don Drysdale, 1-0, in Game 4. The Orioles swept the series.

In the 1969 league championship series, he pitched an 11-inning, 11-strikeout, 1-0 shutout against the Minnesota Twins. A low point in his career came in that year's World Series, when he was lifted from Game 5 in the eighth inning after failing to hold a three-run lead. The New York Mets went on to win that game and the series.

In the 1970 World Series against the Cincinnati Reds, Mr. McNally is remembered not so much for his pitching as his hitting. He made history in the sixth inning of Game 3 when he became the only pitcher to hit a grand slam home run in a World Series game. He got the hit off losing pitcher Tony Cloniger, and he went on to win the game, 9-3.

In 1974, Mr. McNally, along with outfielder Rich Coggins and minor leaguer Bill Kirkpatrick, were traded to the Expos for outfielder Ken Singleton and pitcher Mike Torrez.

In June 1975, after starting the season 3-6 in 12 starts, Mr. McNally announced his retirement from baseball and returned to his native Montana.

But the last chapter of his baseball biography was yet to be written.

Neither the Curt Flood Supreme Court case nor a short 1972 players' strike had managed to resolve the players' greatest complaint: that they had no leverage with their employers. A team and player negotiated knowing that the player could either sign with his team or not play baseball. The player did not have the recourse others had -- to take their skills to another employer.

Pitcher Andy Messersmith refused to sign his contract with the Los Angeles Dodgers, and the Major League Baseball Players Association had filed a grievance, trumpeting that the Dodgers had no right to renew his contract and hold him to that contract for all time.

Eventually, the Dodgers agreed to Messersmith's demand for a salary increase but would not meet his other demands. Union chief Marvin Miller approached Mr. McNally, who though technically retired had had his contract automatically renewed by the Expos. Miller asked Mr. McNally to become a party to the suit.

"He was a really bright guy," Miller told the Associated Press yesterday. "He said, 'You want insurance and I'll be glad to give it to you.' So he joined the grievance. He didn't hesitate for a second. His contribution was a great one."

Peter Seitz, an arbitrator, agreed with the pitchers. On Dec. 23, 1975, he overturned baseball's reserve clause, causing owners and the union to cut a new labor agreement. Players could become free agents, free to sign with other teams, after their fifth major league season.

The results of this decision have been as momentous as they have been controversial. What is undisputed, however, is that the players, who claimed that they were underpaid, have seen their average annual salaries increase from $44,000 in 1975 to $2.38 million today.

Upon learning of Mr. McNally's death, Orioles owner Peter G. Angelos said, "Dave was part of the foundation of this franchise.

"His impact on baseball, through his testing of the reserve clause in 1975, left an indelible mark for which all Major League Baseball players should be indebted to him."

Donald Fehr, who succeeded Miller as head of the players union in 1986, said of Mr. McNally: "His courage and determination led him, along with Andy Messersmith, to challenge a flawed system and thus helped pave the way to improved working conditions for all athletes."

Dave McNally with career memorabilia at home in Billings, Mont. He played for the Orioles for 13 seasons.The three-time all-star helped the Baltimore Orioles win four pennants and two World Series titles. He had a lifetime earned run average of 3.24.