There was the Australian appetizer 10 days ago, and the sneak preview on Sunday night from San Diego.

But it wasn't until Monday that it felt official.

Baseball's regular season has begun.

March 31: Marlins 10, Rockies 1
W: Fernandez   L: De La Rosa  
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Opening Day MLBlog

Finally.

Never does come quick enough, does it?

Sure, by the end of the World Series, everybody is ready for a chance to rest and relax. But by the time the New Year's celebrations have ended, the anticipation begins about baseball's next season.

There are always a few tweaks to the game, like the expansion of instant replay this season. Three times in the early games on Monday, the replay officials were put to work. They even overturned an infield single for Ryan Braun in Milwaukee and overturned another play and called Emilio Bonifacio of the Cubs out.

Braun did, however, receive a warm reception from the fans at Miller Park, welcoming him back after a season marred by injury and a season-ending 65-game suspension for violating baseball's drug policy.

But really, not much changes. Every team has hopes.

Half of them walk away disappointed on Opening Day.

Yes, it is a 162-game season. Yes, all games are equal in the final standings. Nothing, however, is quite like an Opening Day.

The ballpark is dressed up. It's OK to play hooky for a day.

Summer is just around the corner.

So let's push aside the Dodgers' two-game sweep of Arizona in Australia, and for a moment even ignore San Diego's rally for a 3-1 victory against Los Angeles at Petco Park on Sunday night when pinch-hitter Seth Smith, in his first swing of the bat for the Padres, delivered the game-tying home run to start the eighth-inning rally.

It's nothing like Monday.

Twenty-five teams took the field for the first time in a game that counts in 2014, and Arizona got its first chance to spit out the bitter taste of those two games in Australia with its home opener.

There are special moments such as the Neil Walker walk-off home run that lifted Pittsburgh to the 1-0, 10-inning victory over the Cubs. Walker's the kid who has been a Pirate at heart since birth, born and raised in Pittsburgh, his dad a onetime Pirate whom Roberto Clemente talked out of being a part of the mercy flight that crashed and took Clemente's life.

And the new guy in town came to the rescue in Detroit. Veteran Alex Gonzalez, acquired a week earlier from Baltimore after projected shortstop Jose Iglesias was sidelined with stress fractures in both shins, went from a goat to a hero in the span of five innings. It was his error that led to Kansas City's game-tying three-run fourth, his first triple in two years and 363 days that tied the game in the seventh, and his walk-off single that brought the 4-3 Tigers victory to an end in the ninth.

But then there was a lot of newness in Detroit, where Torii Hunter and Miguel Cabrera, hitting second and third, were the only lineup holdovers on a Tigers team with a made-over infield, Cabrera is the only infielder back from a year ago, but he has moved across the diamond from third base to first, in place of Prince Fielder.

That's what Opening Day is about, memories.

There was Bob Feller throwing the only Opening Day no-hitter with Cleveland back in 1940; and Hank Aaron delivering home run No. 714, which tied Babe Ruth's career record, on Opening Day with Atlanta in Cincinnati back in 1974; and Walter Johnson's 1-0, 15-inning victory against the Philadelphia A's in 1910, one of nine shutouts Johnson threw on Opening Day, accounting for all the wins of his 9-5 Opening Day career record.

And on Monday, there was St. Louis' 1-0 victory at Cincinnati, the first time the Reds had been shut out on Opening Day since 1953, when the Braves, in their first game with Milwaukee as their hometown, claimed a 2-0 victory behind the three-hit, no-walk effort at Crosley Field against a team managed by Rogers Hornsby.

With his grandmother watching him pitch professionally for the first time, Cuban right-hander Jose Fernandez equaled a Marlins Opening Day record with nine strikeouts in only six innings of a 10-1 victory against Colorado that was wtinessed by a Marlins Park record crowd of 37,116.

It's Opening Day. Last year is a memory. Spring Training was a blip on the radar.

So the Phillies stumbled offensively in Florida, so what. They broke out the bats on Monday in Arlington and pounded out a 14-10 victory over the Rangers thanks in part to the 200th career home run for Jimmy Rollins, who equaled Cal Ripken's record with his 14th consecutive Opening Day start at shortstop.

And sometimes the past cannot be forgotten, like in Anaheim, where Mike Trout, on the third pitch he was thrown by Seattle's Felix Hernandez, unloaded a two-run home run. It was Trout's 16th hit in 41 career at-bats against the Mariners' ace.

It is just one game in a schedule of 162 games.

But it's different from all the others.

It's the opener.

It's the beginning to a summerlong marathon.