ST. PETERSBURG -- Through the course of a long season, even the best teams have a clunker or two, and they come without warning.
The Red Sox had one on Thursday night at Tropicana Field, taking a 6-3 loss to the Rays in the finale of a three-game series after they won the first two.
The defense made a collection of misplays in the first two innings. And on a night Rick Porcello struggled, the Red Sox paid the price.
"I wasn't sharp at all," Porcello said. "I think -- and it's probably true of any starting pitcher or any pitcher in general, you know -- any time I've struggled this year, it's been a result of falling behind hitters. It happened tonight. I got into some bad counts against guys, started coming in the zone with some pitches, and you get hurt by that."
After going 5-0 with a 2.14 ERA in his first seven starts, Porcello is 1-2 with a 7.29 ERA his last four.
"It's baseball. That's pitching," said Porcello. "You're going to have ebbs and flows over the course of the season, and you've got to make the necessary adjustments and get back on track."
On many nights, the high-powered offense could keep Boston in a game like this. But Rays lefty Blake Snell (six shutout innings, three hits, eight K's) was brilliant.
Down, 6-1, Boston mounted its first significant rally in the ninth. Mitch Moreland led off with a solo shot to right. With the Red Sox down to their last strike, Rafael Devers drilled an RBI double, forcing the Rays to go to closer Alex Colome, who earned the save.

It could have been a different night if not for Porcello's tough start, as Boston fell behind, 6-0, after four innings.
Porcello (6-2, 3.74 ERA) gave up eight hits and six runs (four earned) over 3 2/3 innings, throwing a whopping 92 pitches in that span.
The sinkerballer threw 33 pitches in a two-run first inning, as left fielder J.D. Martinez misplayed a leadoff double by Denard Span and a lined single by Daniel Robertson. According to Statcast™, there was a catch probability of 50 percent on the Span hit and 95 percent on the hit by Robertson. Catcher Sandy Leon added to the mess, dropping a throw to the plate on what would have been a forceout, allowing Wilson Ramos to score the Rays' first run.
"The first inning was what it was, but there was absolutely no reason to go out there and have a long second inning," Porcello said. "I got out of the first inning, honestly, pretty lucky for them to only score two runs and then after that, it's time to get back on track and bear down. I had a long second inning, too, and just didn't get it going. It's on me. I've got to do better than that."
With the bases loaded and two outs in the second, Porcello gave up a full-count single to Ramos that was going to score two runs anyway. But a third run wound up scoring when cutoff man Eduardo Nunez dropped a low throw by right fielder Mookie Betts. It was Betts who wound up being charged with the error.
"I mean, Sandy locked himself up, he'll tell you. Instead of like a first baseman, he was there with the wrong foot and didn't have the freedom to adjust to the throw," said manager Alex Cora. "The throw by Mookie short-hops Nunez. He has to make a better throw, but at the same time, Nunie has to do a better job reading it. Either go get it or move back. It wasn't one of our best defensive efforts."
Despite the defeat, the Red Sox head home leading the Yankees by one game in the American League East and in possession of baseball's top record (34-16).
MOMENTS THAT MATTERED
Moreland's homer in the ninth was his seventh of the season in just 103 at-bats. With Moreland contributing just about every time he plays, and Hanley Ramirez without a hit in his last 21 at-bats, perhaps Cora will make some adjustments with the alignment at first base, at least for the short term.

"We'll see. He put good at-bats together," Cora said of Moreland. "As you guys know, we try to get him at-bats somehow, someway. We like what we see from Jackie [Bradley Jr.] right now, he's putting good at-bats together, he's hitting the ball solid, fouling balls off. It would be hard for me right now to take him out of the lineup because of the rhythm, and it seems like what we're working on before the game is paying off. We'll see. We'll figure it out. We'll find at-bats for Mitch."
SOUND SMART
The Red Sox are starting to get some offense from catcher Leon, who is getting more playing time. Leon has reached base multiple times in his last four starts and has a five-game hitting streak. Over that span, he is 7-for-16. Christian Vazquez, Boston's other catcher, has been in a season-long slump.
HE SAID IT
"It all comes down to plate discipline. It's just about being disciplined, staying off the edges, looking for pitches over the middle of the plate, don't chase hits, that's the bottom line. The hits will come, but it starts with the process. ... Sometimes it's hard for them to accept it. They hit the ball hard, and they want results but no, no, you've got to be disciplined enough to stay within the plan, look for pitches in the middle of the zone. If they don't come at you, take your walks. Right now it's about discipline." -- Cora, on what is ailing Ramirez
MITEL REPLAY OF THE DAY
The Rays tried to extend their lead in the bottom of the sixth when Matt Duffy attempted to score from second on a grounder. Red Sox first baseman Moreland fired home, and Duffy was initially ruled safe, But after the Red Sox challenged, the replay official ruled that Leon tagged Duffy's right leg before Duffy touched home.

UP NEXT
The Red Sox will activate veteran second baseman Dustin Pedroia from the disabled list on Friday, and he may start the 7:10 p.m. ET opener of a three-game series at Fenway Park. Left fielder Andrew Benintendi, who got a night off Thursday, will be back in the lineup. Lefty Eduardo Rodriguez (4-1, 4.13 ERA) will start, and he'll be opposed by Braves righty Julio Teheran (4-1, 4.17 ERA).