These two contenders play 17 more times this season, but it was important for the Rays to make their point early and that's exactly what they did.
Carlos Pena, who gave the Rays a 4-0 lead against CC Sabathia with a grand slam in the first inning, scorched a long single off Rivera with the bases loaded in the ninth, propelling the Rays to their stunning come-from-behind walk-off victory.
This was October baseball in April. The managers, the Rays' Joe Maddon and the Yankees' Joe Girardi, played it like a chess match. With the wheels churning from both dugouts, it could easily have been the seventh game of a World Series.
But in the end, when the Rays seemed to have little hope against the invincible Rivera, they pulled off another of their patented miraculous finishes.
It was a fitting encore to their 8-7 walk-off win in the 12th inning over the Yankees last Sept. 28 that gave them the AL Wild Card. They made that happen by rallying from a 7-0 deficit in the eighth inning.
It's a long, grueling road between April and October, but I believe Game 1 of the 2012 season defined what the Rays are all about and why anything short of the postseason will be a huge disappointment.
Against the Yankees, it was so important, because the Bombers have been to the postseason 16 of their past 17 seasons, 12 times as AL East champs. And don't forget their 27 World Series titles.
"For the first game of a season, there was a lot of stuff going on," said Maddon. "It was definitely thick from both sides. There's no comparison between Spring Training and what happened tonight."
Before Pena ripped his game-winning single on a 1-2 Rivera pitch, the 42-year-old closer was 60-for-61 in save opportunities against the Rays, including 27 in a row before Friday's meltdown. His only other blown save against Tampa Bay came on Aug. 16, 2005, at Tropicana Field, when he walked Jonny Gomes with the bases loaded to give the Rays a 4-3 victory.
Oh, the Rays have now won five straight games against the Yankees.
"I felt good," said Rivera. "I'm not going to make an excuse for it. I just left the ball up on the plate. Up by one run, heart of their lineup. You give them a lot of chances when you pitch like that. You don't want to start a season this way, thank God it's only one game."
Maddon said, considering Rivera's record, the outlook wasn't very bright.
"It's not how you draw it up," sighed Girardi. "You feel pretty good when you have your closer, especially when it's Mo."
After failing to score in the fifth and the eighth with a runner on third and none out and with Rivera on the mound, many in the sellout crowd of 34,078 at the Trop could predict the outcome.
Rivera, however, gave up a leadoff single up the middle to Desmond Jennings -- an at-bat Maddon called key to the inning. Ben Zobrist followed with a booming triple that evened the score at 6. Fans heading for the exits decided to wait a little longer.
With nobody out and Zobrist on third, Girardi ordered the bases loaded with two intentional walks. The Yankees skipper also sent in Eduardo Nunez as an extra infielder in the place of right fielder Nick Swisher.
Rivera, with his cutter working, struck out Sean Rodriguez for the first out and was ahead of Pena.
After spending 2011 with the Cubs, Pena was signed as a free agent during the offseason, returning to Tropicana Field -- the scene of his greatest moments in baseball. He was an integral part of the Rays who made it to the 2008 World Series against the Phillies.
"It's no secret how incredible Rivera is," said Pena. "He's the best closer ever, in the history of the game. We're very aware of that. I have not sniffed the ball against him in the past. I say that very comically. Sometimes we take things too seriously. I was just trying to be as loose as possible.
"I just wanted to get a good pitch to hit, because he has that cutter, which is almost impossible. To be able to put the bat on the ball and drive to left-center and win the ballgame is very special, but we had some pretty good at-bats before that."
When Pena blasted his first-inning slam against Sabathia, the outburst in the stands was so loud it rattled dishes in Bradenton, Fla.
"I am so grateful for a day like today," he said. "I'm happy to get the win, but to get it in such a way is something that I'll never forget."
An hour after the celebration ended on the field, Maddon was still abuzz.
"You have to be on top of your game every night you play in this division," said Maddon. "I'm not suggesting anybody takes a night off, but they're so good all the way around. There's not a weak point in the Yankee team. You better bring our 'A' game."
Pausing he added: "This is life in the fast lane, man. It's cool. I love it. I think it's great."