The game that likes to call itself the national pastime may no longer enjoy the near-monopoly it once held on American sports fans. But baseball's uncanny grip on the general public remains intact. And never is this more apparent than in the annual springtime rite of ''opening day.''
No other sport has anything remotely comparable to the way baseball is able to generate so much excitement by the simple act of beginning its season - as it does today and tomorrow throughout the land. But then no other sport is so deeply imbedded in the nation's folklore and traditions that it reaches out not only to serious or even casual fans, but to millions more who normally couldn't care less about athletic events.
And if the epitome of this phenomenon is seen each October at World Series time, the next closest such moment comes on that chilly day in April when an umpire first calls out the time-honored phrase, ''Play ball!''
The games may not have any special significance - they are, after all, only the first of 162 each team will play during an arduous, six-month schedule. But through the years the day itself has taken on a symbolism far beyond the importance of anything that is happening on the field. It has become, as author Roger Angell once so aptly put it, ''a ceremony of renewal and welcome - a celebration of the simultaneous return of springtime and baseball time, a brief moment of pure hope, and a noisy, cheering restoration of the bonds of loyalty and affection that bind the fans to their home club, and vice versa.''
And so it will be again over the next two weeks at 26 flag-bedecked ballparks stretching throughout this country and into Canada as the 1983 season gets under way. And buoyed by the ''hope that springs eternal,'' fans in all of those cities are filled at least momentarily with an air of expectancy and optimism as they wait for the answers to all those questions they've been asking since last fall.
Can the St. Louis Cardinals and/or the Milwaukee Brewers repeat their successes of last season - something no pennant winner in either league has done since 1978? Or will the the shifting sands of the modern free-agent era swing the pendulum of power in another direction once again - and if so, which one?
Will Billy Martin really last a full season in his third go-'round as New York Yankee manager? And will owner George Steinbrenner's annual barrage of off-season moves - topped by signing free-agent sluggers Don Baylor and Steve Kemp in addition to rehiring Martin - lift his team back to its accustomed role as a top contender?
What will baseball be like without Earl Weaver? How will his erstwhile Baltimore team, which took Milwaukee down to the final day of the 1982 season, fare under new manager Joe Altobelli? Conversely, how solid are the Brewers, heading into the season with ace reliever Rollie Fingers and top starter Pete Vuckovich both question marks due to physical problems?
Will Steve Garvey's arrival transform San Diego into a bonafide pennant threat? What will his departure mean to the Los Angeles Dodger team he anchored for so long? Are the Atlanta Braves for real, or was last year's streaky roller-coaster ride to the National League West title primarily attributable to the lackluster play of the rest of the division?
Can the White Sox, bolstered by much-sought-after free-agent left-hander Floyd Bannister, give Chicago its first pennant since the 1950s? Will the arrival of disciplinarian Bill Virdon as manager finally push Montreal over the top and give the game its first international World Series?
These are but a few of the many intriguing questions that come readily to mind. The answers, of course, will take a while to learn - some of them perhaps the entire six months. Meanwhile, as always, there are sure to be many exciting moments - both of the predictable and the unpredictable variety.
Among the former are the usual individual milestones being approached.
Pete Rose needs only 131 hits to become the second man to reach 4,000 as he continues his relentless march toward Ty Cobb's record of 4,191, which he figures to reach sometime in 1984. Meanwhile his Philadelphia teammate Steve Carlton, who has averaged approximately 20 victories a year for more than a decade, seems a cinch to get the 15 he needs to reach 300 - a feat accomplished only 14 times in major league history and just four times in the last half century (by Lefty Grove, Warren Spahn, Early Wynn, and Gaylord Perry).
Much earlier than any of this - possibly even in his first start, and surely in his first two or three - Nolan Ryan will become the all-time strikeout king. The Houston Astros' fireballer starts the season with 3,494 whiffs of opposing batsmen, thus needing only 14 to tie and 15 to break Walter Johnson's 56 -year-old career mark of 3,508. And of course there is Boston's Carl Yastrzemski, who will become the all-time leader in games played if he appears in 110 contests, and who in any case will continue to add to the many career records he already holds as he plays what he has said will be his farewell season.
It all begins today with one game in each league. Cincinnati, by virtue of its stature as the oldest major league team, has traditionally had the honor of opening the season, and will do so again at 2 p.m. (EST) against Atlanta. But the American League no longer waits a full day to get its own show under way, and as in other recent years, it will start later the same day - this time deferring to Cincinnati for only five minutes before Kansas City meets the Orioles in Baltimore at 2:05 p.m.
Two more American League openers - Cleveland at Oakland and Chicago at Texas - will be played tonight. Then all the other teams in both leagues swing into action Tuesday and Tuesday night. Only half of the teams can start in their own parks, of course, with the rest staging home openers on later dates during the next couple of weeks. The Cardinals get a home date this year, launching defense of their world championship against the Pittsburgh Pirates Tuesday afternoon in St. Louis. The Brewers, however, begin their quest for another American League pennant with nine straight road games. They open Tuesday night in California against the same Angels whom they defeated in the playoffs last October, and don't return to Milwaukee until an April 15 meeting against Kansas City, which is the last of all 26 home opening dates.
Tomorrow: the division races.