ST. PETERSBURG — Kevin Kiermaier did his part, delivering his first professional grand slam in a four-hit night. So did Alex Cobb, pitching into the seventh for the first time in nearly a month. Relievers Grant Balfour, Jake McGee and Brad Boxberger all pitched in.That got the Rays to the ninth inning Wednesday with a two-run lead in a game they had to have to maintain their streak of winning series, their momentum and their renewed hope of salvaging the season.But for it all to work, and to really matter, manager Joe Maddon has said, everyone on the team must do his job. "I can't emphasize enough that we have to all contribute and not just several guys," he said.Joel Peralta didn't, faltering to start the ninth, allowing a single and a one-out walk. Then rookie Kirby Yates, thrust into the toughest situation of his 11-game major-league career, failed, allowing a three-run homer to Salvador Perez.And what looked to be another inspiring win instead turned into a cruel, crushing defeat for the Rays, 5-4."It stings a little bit," Yates said. "Obviously it's a game we should have won. We needed to win. Every W, every win is kind of crucial right now. Obviously it doesn't feel good to be in that situation and let your team down."The loss was just the Rays' third in their past 12 games, but with series wins their new currency, it was costly, ending their streak at three. They dropped back to 42-52 and stayed nine games behind the American League East-leading Orioles.Maddon said he had no regrets about putting Yates, the 27-year-old called up a month ago for his first look, in such a treacherous situation. "He's been a closer at Triple A, he has great stuff," Maddon said. "He put a pitch in a bad spot and we lost the game."But he also said his original plan — after intentionally limiting the workload for Balfour (who faced two batters and got one out), McGee (three and one) and Boxberger (two and two) — was for Peralta to close the ninth. And it was when that didn't work that he went to Yates to face two right-handed hitters, Santana lofting the ball just over the short wall in the leftfield corner, 330 feet of heartbreak. (Juan Carlos Oviedo, a more experienced option, was not available due to soreness.)Peralta said his mistake was not getting ahead of the hitters. He allowed a 1-and-1 single to Jarrod Dyson, who stole second and third as Peralta struck out Lorenzo Cain, then he fell behind Eric Hosmer and walked him, leading to Yates being summoned.The way Maddon saw it, it was the unproductive offense — 1-for-9 with runners in scoring position, 11 left on — that put them in this situation.Then it was a two-out single by Cain in the seventh that prompted the bullpen shuffle. He didn't want Cobb to face Hosmer, who had been swinging well against him, so he had to summon Balfour to finish the seventh.Then he brought in McGee to start the eighth but didn't like how his best reliever looked: "Jake's been over-extended, I didn't see the same stuff.So then he went to Boxberger, whom he didn't want to use at all, to get through the eighth. And that led to Peralta starting the ninth, and that led to trouble, a silent locker room and a noticeable sense of loss."This one is bad," Peralta said. "It really hurts."