Moore is coming off a career-low 4 1/3-inning start Saturday in a 5-3 loss to the Orioles in which he allowed four runs (one earned) on four hits with four walks and six strikeouts. The Rays' defense committed five errors behind him.
He's only thrown 19 1/3 innings over his last four starts, averaging 5 2/3 innings this season while also averaging 104 pitches.
The southpaw is having trouble getting deep into games, as he's thrown at least 100 pitches but failed to record seven innings pitched in each of his seven starts.
No other starter in baseball has done that more than five times this year. He's averaging 18.7 pitches per inning, the third most in the American League.
It has been a rough start to the season for Moore, who along with the Nationals' Bryce Harper and the Angels' Mike Trout, was ranked among the top young prospects in baseball.
Rays manager Joe Maddon hasn't lost faith in his young right-hander.
"He has a great fastball, he just doesn't know where it's going all the time quite yet," Maddon said. "I've seen that before with our other young pitchers, so he's going to be fine."
Moore makes it sound as if his problems are not complex in nature.
"There were just certain pitches in certain counts where I didn't do the things I needed to do as far as going through the process of getting the ball over the plate and in the zone," he said of his troubles in previous starts.
"I feel good. There's a lot of at-bats in the games where they go my way and I make three or four pitches and get outs. I'm having quick innings and throwing up zeros. Just the last couple starts, I've had some crooked numbers up there in one or two big innings."
Doubront, who is 3-1 with a 4.46 ERA in seven starts this season, has won three of his last four starts.
He allowed one run, three hits and struck out five over six innings in his last start in a 4-1 victory over the Indians.
It was his best start of the season and part of five consecutive quality starts by members of Boston's rotation.
"You know, you just try to keep the ball rolling," said Red Sox manager Bobby Valentine. "I think we all might have said early that we're going to be as good as our starting pitching, and everyone wondered about the Nos. 4 or 5 guys, and that's kind of settling in. Now the [Nos.] 1, 2 and 3 guys are healthy and settling in, and that could be the good news."
Doubront's victory in his last outing was his second straight and he has pitched at least six innings in four of his last five starts.
Red Sox: Saltalamacchia hitting well
Jarrod Saltalamacchia was 2-for-4 Wednesday and now has hit safely in 14 of his last 16 starts at a .359 clip (23-for-64). But with the Rays starting a lefty, it's like Kelly Shoppach will get the call in the series finale.
Rays: Home cooking
Following their 2-1 win Wednesday, the Rays are a Major League-best 14-3 at home.
The Rays have committed 32 errors this season, fifth most in the Majors, and are on pace for 136 errors after committing a Major League- low 73 errors last year. They had 14 errors at this point last year.