ST. PETERSBURG -- What was shaping up as the elation of a rookie manager winning his first game swiftly turned into the sting of a stunning defeat.
The bridge to closer Craig Kimbrel collapsed on Alex Cora in his debut as the manager of the Red Sox, and the result was 6-4 loss to the Rays that thrilled the cowbell-clanging fans at Tropicana Field.
"It's baseball," Cora said. "We know it's going to happen [sometimes]. I guess get it out of the way right away."
Denard Span's three-run triple to right was the crushing blow, as the Rays scored six in the bottom of the eighth.
If you're wondering why Cora didn't go to Kimbrel with the game slipping away, it's due to the closer having an abbreviated Spring Training (just two appearances), and it had been decided prior to the game he wouldn't pitch before the ninth.
Still, few people could have seen this coming.

Ace Chris Sale had been magnificent for the Red Sox, staking his team a 4-0 lead with six innings of one-hit ball that included nine strikeouts.
"It's easy to get discouraged -- down 4-0 and Chris Sale just kind of carved us up there for a couple of innings -- and the guys did not," Rays manager Kevin Cash said.
Matt Barnes took care of the seventh flawlessly, and Boston was just six outs away from a satisfying victory on Opening Day.
But on came Joe Kelly in the bottom of the eighth, and then Carson Smith, and it all fell apart.
With a four-run lead, Kelly walked the first batter he faced, Daniel Robertson. After a strikeout of Rob Refsnyder, Kelly allowed an RBI double to Matt Duffy. It still seemed the Red Sox were in good shape, up 4-1 and in need of just five outs. But Kelly didn't get any more. He walked Kevin Kiermaier and Carlos Gomez to load the bases with one out, and that was the end of his outing.
"That's pretty pathetic what I did," Kelly said. "Can't do that. I don't think I've ever done it, and it's probably going to be the last time."
In Kelly's 69th relief appearance as a member of the Red Sox, this was the first time he had walked more than two batters.
Smith came in but, like Kelly, had trouble locating the strike zone, as he walked Brad Miller to force in a run. Then came the game-breaking hit, as Span smashed a three-run triple to right to put the Rays up, 6-4.
"My command was a little off," Smith said. "Fastball was all right. Slider, I got in trouble with Span. I had him down 1-2, had two opportunities to put him away and I didn't."

The game brought back memories of the last time the Red Sox opened a season at Tropicana Field back in 2003, when Pedro Martinez staked the team to a 4-0 lead and Chad Fox surrendered a walk-off, three-run homer to Carl Crawford. The game ended with the same 6-4 score as Thursday. The 2003 Red Sox went on to win 95 games.
"We've got 161 more," said Red Sox right fielder Mookie Betts. "It isn't our first loss and it won't be our last. Sale pitched a great game. We've just got to score some more runs."
MOMENTS THAT MATTERED
Nunez gives Red Sox a thrill: When the ball left Eduardo Nunez's bat in the second inning, it looked like a flyout to left-center. But everything got chaotic when left fielder Span and Kiermaier converged and didn't communicate properly. Span went to the ground first, and Kiermaier then tripped over him and fell. The ball kept rolling, and Nunez roared all the way around the bases in 15.87 seconds, per Statcast™. He dived headfirst into home and gave himself the safe sign upon landing. The Boston bench erupted, as the two-run homer made it a 3-0 game.
"He got the first home run on our team," said Red Sox shortstop Xander Bogaerts. "I know not a lot of people probably expected an inside-the-parker, but he definitely did. He plays all out."

Bogaerts doubled off: The Red Sox hoped to extend their lead in the third when Bogaerts had the second of his three hits on the day, a single to left-center. But when Rafael Devers hit a liner to right, Bogaerts was doubled off first on a nice throw by Gomez.
"That's a tough one," Red Sox manager Alex Cora said. "I talked with [bench coach] Ron Roenicke about it. ... It's a tough read because, if the ball falls, and he short-hopped it, he's probably out at second."

Early sign of trouble? Perhaps it was a bad omen for the Red Sox when Betts led off the game by stinging the first pitch of the season to deep center, only to watch Kiermaier make a tremendous catch at the wall.
"I mean, I was like, 'What's new?'" Betts said. "I think I've hit three or four balls out in that area, and I think it's gotten caught every time. Maybe I should try hitting it somewhere else."

QUOTABLE
"Hey, man, you show up to win, obviously. But things like that happen. That's why we play the game, right? Don't ever take it for granted. It's never over. Just take it off the chin and come back tomorrow ready to go." -- Sale
SOUND SMART WITH YOUR FRIENDS
The last time the Red Sox blew a lead as large as four runs on Opening Day? That aforementioned contest at Tropicana Field, on March 31, 2003. Last season, the Red Sox never blew a lead of more than three runs.
WHAT'S NEXT
Red Sox: Friday will almost feel like a second Opening Day for the Red Sox, as left-hander David Price makes his anticipated debut after being limited to 11 starts last season due to elbow woes. Price felt great during Spring Training and is optimistic that he can regain his status as one of the best starting pitchers in the game.
Rays: The new and improved Blake Snell will make his first start of the season after dominating during the spring. The talented left-hander ended 2017 on a high note, going 5-1 with a 2.84 ERA in his final 10 starts. He is 1-3 with a 5.95 ERA in four career starts against the Red Sox and has lost three straight starts against them. First pitch is scheduled for 7:10 p.m. ET.
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